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timestamp[us]date 1999-12-11 03:00:00
2025-04-28 00:58:08
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---|---|---|---|---|---|---|---|---|---|---|---|---|
A381425 | Square array A(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of (1 + x/(1-x)^k)^k. | [
"1",
"1",
"0",
"1",
"1",
"0",
"1",
"2",
"1",
"0",
"1",
"3",
"5",
"1",
"0",
"1",
"4",
"12",
"10",
"1",
"0",
"1",
"5",
"22",
"37",
"18",
"1",
"0",
"1",
"6",
"35",
"92",
"102",
"30",
"1",
"0",
"1",
"7",
"51",
"185",
"345",
"258",
"47",
"1",
"0",
"1",
"8",
"70",
"326",
"880",
"1188",
"606",
"70",
"1",
"0",
"1",
"9",
"92",
"525",
"1881",
"3851",
"3796",
"1335",
"100",
"1",
"0",
"1",
"10",
"117",
"792",
"3563",
"10002",
"15655",
"11364",
"2781",
"138",
"1",
"0"
] | [
"nonn",
"easy",
"tabl"
] | 109 | 0 | 8 | [
"A000007",
"A000012",
"A000326",
"A001477",
"A071919",
"A096000",
"A177787",
"A362125",
"A381425",
"A382859"
] | null | Seiichi Manyama, Apr 07 2025 | 2025-04-11T12:09:07 | oeisdata/seq/A381/A381425.seq | 8ba0130287b43de760cd6171481b50ea |
A381426 | A(n,k) is the sum over all ordered partitions of [n] of k^j for an ordered partition with j inversions; square array A(n,k), n>=0, k>=0, read by antidiagonals. | [
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"3",
"4",
"1",
"1",
"4",
"13",
"8",
"1",
"1",
"5",
"36",
"75",
"16",
"1",
"1",
"6",
"79",
"696",
"541",
"32",
"1",
"1",
"7",
"148",
"3851",
"27808",
"4683",
"64",
"1",
"1",
"8",
"249",
"14808",
"567733",
"2257888",
"47293",
"128",
"1",
"1",
"9",
"388",
"44643",
"5942608",
"251790113",
"369572160",
"545835",
"256",
"1",
"1",
"10",
"571",
"113480",
"40065301",
"9546508128",
"335313799327",
"121459776768",
"7087261",
"512"
] | [
"nonn",
"tabl",
"changed"
] | 23 | 0 | 6 | [
"A000670",
"A011782",
"A289545",
"A347841",
"A347842",
"A347843",
"A347844",
"A347845",
"A347846",
"A381299",
"A381369",
"A381426",
"A381427"
] | null | Alois P. Heinz, Feb 23 2025 | 2025-04-19T03:52:59 | oeisdata/seq/A381/A381426.seq | 0d608cf1e6bbe696b3ca3f3e579e6d42 |
A381427 | Sum over all ordered partitions of [n] of n^j for an ordered partition with j inversions. | [
"1",
"1",
"4",
"79",
"14808",
"40065301",
"2099255895008",
"2651651342949844915",
"96254339565438079064819328",
"116387990444553949414146511586296381",
"5327195120249449992420082364255283659438679552",
"10333056290045508772052838892223597279253890797441054043823"
] | [
"nonn"
] | 14 | 0 | 3 | [
"A062173",
"A135528",
"A381299",
"A381373",
"A381426",
"A381427"
] | null | Alois P. Heinz, Feb 23 2025 | 2025-02-23T17:34:42 | oeisdata/seq/A381/A381427.seq | b686ec3f8163766e6b7a27af3b4270af |
A381428 | E.g.f. A(x) satisfies A(x) = 1/( 1 - sinh(x) * A(x)^2 ). | [
"1",
"1",
"6",
"73",
"1344",
"33481",
"1054656",
"40223233",
"1802385024",
"92827015921",
"5403527705856",
"350854589607193",
"25142008355656704",
"1971003462240791161",
"167802783944207917056",
"15417877986778302551953",
"1520661128893781018640384",
"160249491538400609431567201",
"17969682580669053325124960256"
] | [
"nonn"
] | 11 | 0 | 3 | [
"A006154",
"A136630",
"A295254",
"A381428",
"A381429"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T04:19:08 | oeisdata/seq/A381/A381428.seq | 32b3b1903d9d54e3562fa23ab83384f6 |
A381429 | E.g.f. A(x) satisfies A(x) = 1/( 1 - sinh(x) * A(x)^3 ). | [
"1",
"1",
"8",
"133",
"3392",
"117601",
"5167808",
"275334613",
"17250670592",
"1242994578721",
"101273185092608",
"9206681997173893",
"923928346115182592",
"101453787213382443841",
"12100018549609932996608",
"1557645163271323384461973",
"215265839194368088629051392",
"31788685348087376561935104961"
] | [
"nonn"
] | 8 | 0 | 3 | [
"A006154",
"A136630",
"A295254",
"A381428",
"A381429"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T04:20:19 | oeisdata/seq/A381/A381429.seq | e36dadefe446c7445b12e706eec23aeb |
A381430 | E.g.f. A(x) satisfies A(x) = 1 + sinh(x*A(x)^3). | [
"1",
"1",
"6",
"73",
"1368",
"34861",
"1126368",
"44135701",
"2034072960",
"107823563641",
"6463383851520",
"432331180935457",
"31924171503581184",
"2579483385868484005",
"226383845487041421312",
"21445302563389991287981",
"2180974075392495296544768",
"237009522316557393020262001",
"27409082977094100068471537664"
] | [
"nonn"
] | 11 | 0 | 3 | [
"A136630",
"A162653",
"A198865",
"A381430",
"A381443"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T04:21:14 | oeisdata/seq/A381/A381430.seq | b1c4d48e1800fd671c3c31e929d6cdb9 |
A381431 | Heinz number of the section-sum partition of the prime indices of n. | [
"1",
"2",
"3",
"4",
"5",
"5",
"7",
"8",
"9",
"7",
"11",
"10",
"13",
"11",
"11",
"16",
"17",
"15",
"19",
"14",
"13",
"13",
"23",
"20",
"25",
"17",
"27",
"22",
"29",
"13",
"31",
"32",
"17",
"19",
"17",
"25",
"37",
"23",
"19",
"28",
"41",
"17",
"43",
"26",
"33",
"29",
"47",
"40",
"49",
"35",
"23",
"34",
"53",
"45",
"19",
"44",
"29",
"31",
"59",
"26",
"61",
"37",
"39",
"64",
"23",
"19",
"67",
"38"
] | [
"nonn"
] | 10 | 1 | 2 | [
"A000040",
"A000720",
"A001222",
"A001223",
"A003557",
"A003963",
"A005117",
"A047966",
"A048767",
"A048768",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A091602",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A181819",
"A212166",
"A217605",
"A238745",
"A239455",
"A270995",
"A296119",
"A300383",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A380955",
"A381078",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381438",
"A381440",
"A381441",
"A381452",
"A381454"
] | null | Gus Wiseman, Feb 26 2025 | 2025-02-27T22:58:04 | oeisdata/seq/A381/A381431.seq | 7c8815fe2c7fe3202243e14cb9682f8b |
A381432 | Heinz numbers of section-sum partitions. Union of A381431. | [
"1",
"2",
"3",
"4",
"5",
"7",
"8",
"9",
"10",
"11",
"13",
"14",
"15",
"16",
"17",
"19",
"20",
"22",
"23",
"25",
"26",
"27",
"28",
"29",
"31",
"32",
"33",
"34",
"35",
"37",
"38",
"39",
"40",
"41",
"43",
"44",
"45",
"46",
"47",
"49",
"50",
"51",
"52",
"53",
"55",
"56",
"57",
"58",
"59",
"61",
"62",
"64",
"65",
"67",
"68",
"69",
"71",
"73",
"74",
"75",
"76",
"77",
"79",
"80",
"81",
"82",
"83"
] | [
"nonn"
] | 7 | 1 | 2 | [
"A000040",
"A000720",
"A001222",
"A001223",
"A003557",
"A047966",
"A048767",
"A048768",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A212166",
"A217605",
"A238745",
"A239455",
"A239964",
"A270995",
"A296119",
"A300383",
"A317081",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A381078",
"A381431",
"A381432",
"A381433",
"A381436",
"A381437",
"A381440",
"A381441",
"A381452",
"A381454"
] | null | Gus Wiseman, Feb 27 2025 | 2025-02-28T10:35:51 | oeisdata/seq/A381/A381432.seq | 0eb441b914978c55f311fe6553b22e73 |
A381433 | Heinz numbers of non section-sum partitions. Complement of A381431. | [
"6",
"12",
"18",
"21",
"24",
"30",
"36",
"42",
"48",
"54",
"60",
"63",
"66",
"70",
"72",
"78",
"84",
"90",
"96",
"102",
"105",
"108",
"110",
"114",
"120",
"126",
"132",
"138",
"140",
"144",
"147",
"150",
"154",
"156",
"162",
"165",
"168",
"174",
"180",
"186",
"189",
"192",
"198",
"204",
"210",
"216",
"220",
"222",
"228",
"231",
"234",
"238",
"240",
"246",
"252",
"258"
] | [
"nonn"
] | 6 | 1 | 1 | [
"A000040",
"A000720",
"A001222",
"A001223",
"A003557",
"A048767",
"A048768",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A181819",
"A217605",
"A238745",
"A239455",
"A239964",
"A270995",
"A296119",
"A300383",
"A317081",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A381078",
"A381431",
"A381432",
"A381433",
"A381436",
"A381437",
"A381440",
"A381441",
"A381452",
"A381454"
] | null | Gus Wiseman, Feb 27 2025 | 2025-02-28T10:35:48 | oeisdata/seq/A381/A381433.seq | bad3d5dfba2facb599f3511e8ee3dddb |
A381434 | Numbers appearing only once in A381431 (section-sum partition of prime indices). | [
"1",
"2",
"3",
"4",
"8",
"9",
"10",
"14",
"15",
"16",
"20",
"22",
"27",
"28",
"32",
"33",
"35",
"40",
"44",
"45",
"50",
"55",
"56",
"64",
"75",
"77",
"80",
"81",
"88",
"98",
"99",
"100",
"112",
"128",
"130",
"135",
"160",
"170",
"175",
"176",
"182",
"190",
"195",
"196",
"200"
] | [
"nonn"
] | 14 | 1 | 2 | [
"A000005",
"A000040",
"A000720",
"A000961",
"A001222",
"A001223",
"A003557",
"A048767",
"A048768",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A212166",
"A217605",
"A239455",
"A239964",
"A296119",
"A300383",
"A317081",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A381078",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381440",
"A381441",
"A381452",
"A381454",
"A381540",
"A381541"
] | null | Gus Wiseman, Feb 27 2025 | 2025-03-02T22:34:48 | oeisdata/seq/A381/A381434.seq | c0b46c51adcdeffe294fb3631af38942 |
A381435 | Numbers appearing more then once in A381431 (section-sum partition of prime indices). | [
"5",
"7",
"11",
"13",
"17",
"19",
"23",
"25",
"26",
"29",
"31",
"34",
"37",
"38",
"39",
"41",
"43",
"46",
"47",
"49",
"51",
"52",
"53",
"57",
"58",
"59",
"61",
"62",
"65",
"67",
"68",
"69",
"71",
"73",
"74",
"76",
"79",
"82",
"83",
"85",
"86",
"87",
"89",
"91",
"92",
"93",
"94",
"95",
"97",
"101",
"103",
"104",
"106",
"107",
"109",
"111",
"113",
"115",
"116",
"117",
"118",
"119"
] | [
"nonn"
] | 13 | 1 | 1 | [
"A000005",
"A000040",
"A000720",
"A000961",
"A001222",
"A001223",
"A003557",
"A048767",
"A048768",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A212166",
"A217605",
"A239455",
"A239964",
"A296119",
"A300383",
"A317081",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A381078",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381440",
"A381441",
"A381452",
"A381454",
"A381540",
"A381541"
] | null | Gus Wiseman, Feb 27 2025 | 2025-03-02T22:34:33 | oeisdata/seq/A381/A381435.seq | 10ec3159a7055ad768614963ebe5258d |
A381436 | Irregular triangle read by rows where row k is the section-sum partition of the prime indices of n. | [
"1",
"2",
"1",
"1",
"3",
"3",
"4",
"1",
"1",
"1",
"2",
"2",
"4",
"5",
"3",
"1",
"6",
"5",
"5",
"1",
"1",
"1",
"1",
"7",
"3",
"2",
"8",
"4",
"1",
"6",
"6",
"9",
"3",
"1",
"1",
"3",
"3",
"7",
"2",
"2",
"2",
"5",
"1",
"10",
"6",
"11",
"1",
"1",
"1",
"1",
"1",
"7",
"8",
"7",
"3",
"3",
"12",
"9",
"8",
"4",
"1",
"1",
"13",
"7",
"14",
"6",
"1",
"5",
"2",
"10",
"15",
"3",
"1",
"1",
"1",
"4",
"4",
"4",
"3",
"9",
"7",
"1",
"16",
"3",
"2",
"2"
] | [
"nonn",
"tabf"
] | 6 | 1 | 2 | [
"A000005",
"A000040",
"A000720",
"A000961",
"A001222",
"A003557",
"A003963",
"A005117",
"A047966",
"A048767",
"A050320",
"A051903",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A181819",
"A238744",
"A238745",
"A239455",
"A270995",
"A296119",
"A300383",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A380955",
"A381078",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381438",
"A381440",
"A381441",
"A381452",
"A381454"
] | null | Gus Wiseman, Feb 28 2025 | 2025-02-28T23:12:09 | oeisdata/seq/A381/A381436.seq | 876aa593e107d407a29ba6465e8b76e8 |
A381437 | Last part of the section-sum partition of the prime indices of n. | [
"0",
"1",
"2",
"1",
"3",
"3",
"4",
"1",
"2",
"4",
"5",
"1",
"6",
"5",
"5",
"1",
"7",
"2",
"8",
"1",
"6",
"6",
"9",
"1",
"3",
"7",
"2",
"1",
"10",
"6",
"11",
"1",
"7",
"8",
"7",
"3",
"12",
"9",
"8",
"1",
"13",
"7",
"14",
"1",
"2",
"10",
"15",
"1",
"4",
"3",
"9",
"1",
"16",
"2",
"8",
"1",
"10",
"11",
"17",
"1",
"18",
"12",
"2",
"1",
"9",
"8",
"19",
"1",
"11",
"8",
"20",
"1",
"21",
"13",
"3",
"1",
"9",
"9",
"22",
"1",
"2"
] | [
"nonn"
] | 6 | 1 | 3 | [
"A000040",
"A000720",
"A001221",
"A001222",
"A001223",
"A003557",
"A008578",
"A047966",
"A048767",
"A050320",
"A051903",
"A051904",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A181819",
"A239455",
"A270995",
"A296119",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A360013",
"A380955",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381438",
"A381439",
"A381440"
] | null | Gus Wiseman, Feb 28 2025 | 2025-03-02T08:02:07 | oeisdata/seq/A381/A381437.seq | b277f0aa7611aa95eb73b0a59d0979d1 |
A381438 | Triangle read by rows where T(n>0,k>0) is the number of integer partitions of n whose section-sum partition ends with k. | [
"1",
"1",
"1",
"1",
"0",
"2",
"2",
"1",
"0",
"2",
"3",
"1",
"0",
"0",
"3",
"4",
"1",
"2",
"0",
"0",
"4",
"7",
"2",
"1",
"0",
"0",
"0",
"5",
"9",
"4",
"1",
"2",
"0",
"0",
"0",
"6",
"13",
"4",
"4",
"1",
"0",
"0",
"0",
"0",
"8",
"18",
"6",
"3",
"2",
"3",
"0",
"0",
"0",
"0",
"10",
"26",
"9",
"5",
"2",
"2",
"0",
"0",
"0",
"0",
"0",
"12",
"32",
"12",
"8",
"4",
"2",
"4",
"0",
"0",
"0",
"0",
"0",
"15"
] | [
"nonn",
"tabl"
] | 6 | 1 | 6 | [
"A000009",
"A000041",
"A047966",
"A047967",
"A048767",
"A050320",
"A051903",
"A051904",
"A066328",
"A089259",
"A091602",
"A116540",
"A116861",
"A122111",
"A181819",
"A212166",
"A239455",
"A241131",
"A270995",
"A296119",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A381431",
"A381432",
"A381433",
"A381434",
"A381435",
"A381436",
"A381437",
"A381438",
"A381440"
] | null | Gus Wiseman, Mar 01 2025 | 2025-03-02T08:01:57 | oeisdata/seq/A381/A381438.seq | ff395d6962a85f0af766bc9858fe8009 |
A381439 | Numbers whose exponent of 2 in their canonical prime factorization is not larger than all the other exponents. | [
"3",
"5",
"6",
"7",
"9",
"10",
"11",
"13",
"14",
"15",
"17",
"18",
"19",
"21",
"22",
"23",
"25",
"26",
"27",
"29",
"30",
"31",
"33",
"34",
"35",
"36",
"37",
"38",
"39",
"41",
"42",
"43",
"45",
"46",
"47",
"49",
"50",
"51",
"53",
"54",
"55",
"57",
"58",
"59",
"61",
"62",
"63",
"65",
"66",
"67",
"69",
"70",
"71",
"73",
"74",
"75",
"77",
"78",
"79",
"81",
"82",
"83",
"85",
"86",
"87",
"89"
] | [
"nonn"
] | 6 | 1 | 1 | [
"A000040",
"A000720",
"A001221",
"A001222",
"A001223",
"A001694",
"A003557",
"A005117",
"A007814",
"A051903",
"A051904",
"A055396",
"A056239",
"A061395",
"A066328",
"A112798",
"A122111",
"A130091",
"A181819",
"A212166",
"A239455",
"A241131",
"A351293",
"A360013",
"A360014",
"A360015",
"A375669",
"A380955",
"A381431",
"A381436",
"A381437",
"A381438",
"A381439",
"A381544"
] | null | Gus Wiseman, Mar 02 2025 | 2025-03-02T16:04:19 | oeisdata/seq/A381/A381439.seq | 608b0b6c99c46bf160269addff79cbbe |
A381440 | Irregular triangle read by rows where row k is the Look-and-Say partition of the prime indices of n. | [
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"3",
"2",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"4",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1"
] | [
"nonn",
"tabf"
] | 6 | 1 | 4 | [
"A000040",
"A000720",
"A001222",
"A003557",
"A003963",
"A047966",
"A048767",
"A048768",
"A050320",
"A051903",
"A051904",
"A055396",
"A056239",
"A061395",
"A066328",
"A071178",
"A089259",
"A091602",
"A112798",
"A116540",
"A116861",
"A122111",
"A130091",
"A181819",
"A212166",
"A217605",
"A238744",
"A239455",
"A270995",
"A296119",
"A300383",
"A317141",
"A318360",
"A318361",
"A351293",
"A351294",
"A351295",
"A380955",
"A381078",
"A381431",
"A381432",
"A381433",
"A381436",
"A381437",
"A381438",
"A381440",
"A381441",
"A381452",
"A381454",
"A381540",
"A381541"
] | null | Gus Wiseman, Feb 28 2025 | 2025-02-28T23:12:04 | oeisdata/seq/A381/A381440.seq | 5b7911016b7e4656f66a81fdeeeda71f |
A381441 | Number of multisets that can be obtained by partitioning the prime indices of n into a set of sets (set system) and taking their sums. | [
"1",
"1",
"1",
"0",
"1",
"2",
"1",
"0",
"0",
"2",
"1",
"1",
"1",
"2",
"2",
"0",
"1",
"1",
"1",
"1",
"2",
"2",
"1",
"0",
"0",
"2",
"0",
"1",
"1",
"5",
"1",
"0",
"2",
"2",
"2",
"1",
"1",
"2",
"2",
"0",
"1",
"5",
"1",
"1",
"1",
"2",
"1",
"0",
"0",
"1",
"2",
"1",
"1",
"0",
"2",
"0",
"2",
"2",
"1",
"4",
"1",
"2",
"1",
"0",
"2",
"5",
"1",
"1",
"2",
"5",
"1",
"0",
"1",
"2",
"1",
"1",
"2",
"5",
"1",
"0",
"0",
"2",
"1",
"4",
"2",
"2",
"2"
] | [
"nonn"
] | 10 | 1 | 6 | [
"A000009",
"A000040",
"A000041",
"A000688",
"A000720",
"A001055",
"A001222",
"A001223",
"A002846",
"A003963",
"A005117",
"A045778",
"A050320",
"A050326",
"A050342",
"A050361",
"A055396",
"A056239",
"A061395",
"A066328",
"A112798",
"A116539",
"A122111",
"A213242",
"A213385",
"A213427",
"A265947",
"A279785",
"A293243",
"A293511",
"A296120",
"A299202",
"A300383",
"A300385",
"A317141",
"A317142",
"A318361",
"A321469",
"A381078",
"A381441",
"A381452",
"A381453",
"A381454",
"A381455",
"A381633",
"A381634",
"A381635",
"A381636",
"A381637",
"A381715",
"A381716"
] | null | Gus Wiseman, Mar 06 2025 | 2025-03-08T12:23:37 | oeisdata/seq/A381/A381441.seq | 5f00bbd82d93e73c1c065706890c7be7 |
A381442 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + sinh(x))^2 ). | [
"1",
"2",
"10",
"86",
"1080",
"18042",
"377936",
"9538622",
"281946496",
"9557102450",
"365548361472",
"15576454300134",
"731807446707200",
"37584596599753322",
"2094995668172597248",
"125966553940498047182",
"8127048592610380578816",
"560040497770823162810082",
"41054563701320694564061184"
] | [
"nonn"
] | 9 | 0 | 2 | [
"A136630",
"A198865",
"A381442"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T04:23:46 | oeisdata/seq/A381/A381442.seq | c2168ba1dd9d517d37e198254bfd95a8 |
A381443 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + sinh(x))^3 ). | [
"1",
"3",
"24",
"333",
"6720",
"179523",
"5992800",
"240498261",
"11287790592",
"607019415075",
"36813049552896",
"2486167829854173",
"185070328813031424",
"15056826823777670883",
"1329283990371617820672",
"126573877370649849898149",
"12930948581449447912243200",
"1410875453109072905123881923"
] | [
"nonn"
] | 13 | 0 | 2 | [
"A136630",
"A377554",
"A381430",
"A381443",
"A381450"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T08:52:31 | oeisdata/seq/A381/A381443.seq | b601525bc709aa853fae408dc7d13d1f |
A381444 | Expansion of e.g.f. ( (1/x) * Series_Reversion( x * exp(-2*x * cosh(x)) ) )^(1/2). | [
"1",
"1",
"5",
"52",
"837",
"18276",
"504673",
"16871632",
"662646281",
"29912003344",
"1526065495101",
"86843677613760",
"5454045493422925",
"374720831464254016",
"27958655248431100313",
"2251304544037066606336",
"194594761915894781438481",
"17971382474574151984603392",
"1766073848394482007514748533"
] | [
"nonn"
] | 9 | 0 | 3 | [
"A185951",
"A381143",
"A381444"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:36:03 | oeisdata/seq/A381/A381444.seq | 73e7bb1e10492676c592ddf2cee36716 |
A381445 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * cosh(x) * A(x)^2 ). | [
"1",
"1",
"6",
"75",
"1392",
"34925",
"1108080",
"42562807",
"1920796416",
"99628495353",
"5840628226560",
"381927689957891",
"27562916396961792",
"2176123474607538469",
"186580455503952427008",
"17264834430223073672175",
"1714909152672462179205120",
"182002038900785304200753777",
"20553746198157175799599202304"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A185951",
"A205571",
"A295256",
"A381445",
"A381446"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:37:07 | oeisdata/seq/A381/A381445.seq | 7600eb86b8652a1178ecd8f24e73cd14 |
A381446 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * cosh(x) * A(x)^3 ). | [
"1",
"1",
"8",
"135",
"3456",
"120245",
"5303040",
"283559227",
"17830210048",
"1289406976713",
"105435719470080",
"9619902621234191",
"968905466782150656",
"106779534666615500989",
"12781543241568143171584",
"1651368425166943566943875",
"229049483642619517308764160",
"33947359023461155854768564497"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A185951",
"A205571",
"A295256",
"A381445",
"A381446"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:37:57 | oeisdata/seq/A381/A381446.seq | 2198172a2776fad634e9c90f29ef324d |
A381447 | E.g.f. A(x) satisfies A(x) = 1 + x*A(x)^2 * cosh(x*A(x)^2). | [
"1",
"1",
"4",
"33",
"432",
"7745",
"175680",
"4818457",
"155138816",
"5738752161",
"239890406400",
"11184338164241",
"575437530083328",
"32387311520034913",
"1979498673768132608",
"130566701113312750665",
"9244392468538216611840",
"699309477932976288024257",
"56289911059840766752456704"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A185951",
"A381171",
"A381447",
"A381448"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:39:11 | oeisdata/seq/A381/A381447.seq | c04f55338578028662da9151f323192b |
A381448 | E.g.f. A(x) satisfies A(x) = 1 + x*A(x)^3 * cosh(x*A(x)^3). | [
"1",
"1",
"6",
"75",
"1464",
"39065",
"1324080",
"54460987",
"2635269504",
"146681897553",
"9233067686400",
"648538095601451",
"50289434320131072",
"4267083467872455529",
"393266542856236148736",
"39121731305087283953115",
"4178124995723585643970560",
"476806534212831941528989217",
"57905078072597558361906610176"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A185951",
"A381171",
"A381447",
"A381448"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:40:16 | oeisdata/seq/A381/A381448.seq | b01de798d3c8dbb113bd52182a2db104 |
A381449 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x * cosh(x))^2 ). | [
"1",
"2",
"10",
"90",
"1224",
"22450",
"517920",
"14395514",
"468414464",
"17474840226",
"735559614720",
"34491849224602",
"1783268816102400",
"100786369113730898",
"6182264844496971776",
"409065938149354422330",
"29043282491002728284160",
"2202461172795524123296834",
"177675452451923238962528256"
] | [
"nonn"
] | 10 | 0 | 2 | [
"A185951",
"A381171",
"A381447",
"A381449",
"A381450"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T05:41:16 | oeisdata/seq/A381/A381449.seq | 4dec183d0f36d465d716bc0ea4371346 |
A381450 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x * cosh(x))^3 ). | [
"1",
"3",
"24",
"339",
"7056",
"195855",
"6819840",
"286105071",
"14055420288",
"791783681499",
"50327779368960",
"3563709848656683",
"278223968271034368",
"23744747385054558759",
"2199369837961901789184",
"219748696455778150645575",
"23559108001707680103628800",
"2697737574531326391439989171"
] | [
"nonn"
] | 12 | 0 | 2 | [
"A185951",
"A377554",
"A381171",
"A381443",
"A381448",
"A381449",
"A381450"
] | null | Seiichi Manyama, Feb 23 2025 | 2025-02-24T08:52:23 | oeisdata/seq/A381/A381450.seq | b59a55624280252bb132c58d9259eec0 |
A381451 | Triangle read by rows: T(n,k) is the clique covering number of the Johnson graph J(n, k), n >= 2, 0 < k < n. | [
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"3",
"3",
"1",
"1",
"4",
"6",
"4",
"1",
"1",
"5",
"9",
"9",
"5",
"1",
"1",
"6",
"12",
"14",
"12",
"6",
"1",
"1",
"7",
"16",
"25",
"25",
"16",
"7",
"1",
"1",
"8",
"20",
"40",
"46",
"40",
"20",
"8",
"1",
"1",
"9",
"25",
"56"
] | [
"nonn",
"tabl",
"hard",
"more"
] | 25 | 2 | 5 | [
"A002620",
"A381451"
] | null | Søren Fuglede Jørgensen, Feb 24 2025 | 2025-03-09T16:50:23 | oeisdata/seq/A381/A381451.seq | e721ba5cba81e7c8d8b63b0a9fcbd545 |
A381452 | Number of multisets that can be obtained by partitioning the prime indices of n into a set of multisets and taking their sums. | [
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"2",
"1",
"2",
"1",
"3",
"1",
"2",
"2",
"2",
"1",
"3",
"1",
"3",
"2",
"2",
"1",
"4",
"1",
"2",
"2",
"3",
"1",
"5",
"1",
"3",
"2",
"2",
"2",
"4",
"1",
"2",
"2",
"5",
"1",
"5",
"1",
"3",
"3",
"2",
"1",
"5",
"1",
"3",
"2",
"3",
"1",
"5",
"2",
"5",
"2",
"2",
"1",
"7",
"1",
"2",
"3",
"4",
"2",
"5",
"1",
"3",
"2",
"5",
"1",
"6",
"1",
"2",
"3",
"3",
"2",
"5",
"1",
"6",
"2",
"2",
"1",
"8",
"2",
"2",
"2"
] | [
"nonn"
] | 11 | 1 | 6 | [
"A000009",
"A000040",
"A000041",
"A000688",
"A000720",
"A001055",
"A001222",
"A001970",
"A002846",
"A003963",
"A045778",
"A050320",
"A050326",
"A050361",
"A055396",
"A056239",
"A061395",
"A066328",
"A112798",
"A122111",
"A213385",
"A213427",
"A261049",
"A265947",
"A293243",
"A296118",
"A299200",
"A299202",
"A300383",
"A300385",
"A317141",
"A317142",
"A317775",
"A317776",
"A318286",
"A321469",
"A381078",
"A381441",
"A381452",
"A381453",
"A381454",
"A381455",
"A381633",
"A381634",
"A381635",
"A381636",
"A381637",
"A381715",
"A381716"
] | null | Gus Wiseman, Mar 06 2025 | 2025-03-08T12:24:03 | oeisdata/seq/A381/A381452.seq | 0dbdf84846f5c84c2b8b3a8a22521bae |
A381453 | Number of multisets that can be obtained by choosing a constant integer partition of each prime index of n and taking the multiset union. | [
"1",
"1",
"2",
"1",
"2",
"2",
"3",
"1",
"3",
"2",
"2",
"2",
"4",
"3",
"4",
"1",
"2",
"3",
"4",
"2",
"6",
"2",
"3",
"2",
"3",
"4",
"4",
"3",
"4",
"4",
"2",
"1",
"4",
"2",
"6",
"3",
"6",
"4",
"8",
"2",
"2",
"6",
"4",
"2",
"6",
"3",
"4",
"2",
"6",
"3",
"4",
"4",
"5",
"4",
"4",
"3",
"8",
"4",
"2",
"4",
"6",
"2",
"8",
"1",
"8",
"4",
"2",
"2",
"6",
"6",
"6",
"3",
"4",
"6",
"6",
"4",
"6",
"8",
"4",
"2",
"5",
"2",
"2",
"6",
"4",
"4",
"8"
] | [
"nonn"
] | 12 | 1 | 3 | [
"A000009",
"A000040",
"A000041",
"A000079",
"A000688",
"A000720",
"A000961",
"A001055",
"A001222",
"A002577",
"A003963",
"A006171",
"A008966",
"A018818",
"A045778",
"A050320",
"A050326",
"A050361",
"A055396",
"A056239",
"A061395",
"A112798",
"A122111",
"A213242",
"A213385",
"A213427",
"A265947",
"A275870",
"A279784",
"A293243",
"A295935",
"A299200",
"A300273",
"A300383",
"A300385",
"A317141",
"A321469",
"A355731",
"A355733",
"A381078",
"A381441",
"A381452",
"A381453",
"A381454",
"A381455",
"A381633",
"A381634",
"A381635",
"A381636",
"A381637",
"A381715",
"A381716",
"A381806"
] | null | Gus Wiseman, Mar 08 2025 | 2025-04-01T11:10:41 | oeisdata/seq/A381/A381453.seq | 5aca27e4cc02443c3a532a4ee0a42e8a |
A381454 | Number of multisets that can be obtained by choosing a strict integer partition of each prime index of n and taking the multiset union. | [
"1",
"1",
"1",
"1",
"2",
"1",
"2",
"1",
"1",
"2",
"3",
"1",
"4",
"2",
"2",
"1",
"5",
"1",
"6",
"2",
"2",
"3",
"8",
"1",
"3",
"4",
"1",
"2",
"10",
"2",
"12",
"1",
"3",
"5",
"4",
"1",
"15",
"6",
"4",
"2",
"18",
"2",
"22",
"3",
"2",
"8",
"27",
"1",
"3",
"3",
"5",
"4",
"32",
"1",
"6",
"2",
"6",
"10",
"38",
"2",
"46",
"12",
"2",
"1",
"8",
"3",
"54",
"5",
"8",
"4",
"64",
"1",
"76",
"15",
"3",
"6",
"6",
"4",
"89",
"2",
"1"
] | [
"nonn"
] | 6 | 1 | 5 | [
"A000009",
"A000040",
"A000041",
"A000688",
"A000720",
"A001055",
"A001222",
"A002846",
"A003586",
"A003963",
"A005117",
"A045778",
"A050320",
"A050326",
"A050342",
"A050361",
"A055396",
"A056239",
"A061395",
"A066328",
"A089259",
"A112798",
"A116539",
"A116540",
"A122111",
"A213242",
"A213385",
"A213427",
"A265947",
"A270995",
"A279785",
"A293243",
"A293511",
"A296119",
"A296120",
"A299200",
"A299201",
"A299202",
"A300383",
"A300385",
"A317141",
"A317142",
"A318360",
"A318361",
"A321469",
"A355733",
"A358914",
"A381078",
"A381441",
"A381452",
"A381453",
"A381454",
"A381455",
"A381633",
"A381634",
"A381635",
"A381636",
"A381637",
"A381715",
"A381716",
"A381717",
"A381718",
"A381806"
] | null | Gus Wiseman, Mar 08 2025 | 2025-03-09T12:29:13 | oeisdata/seq/A381/A381454.seq | 21ac9168fc951997f25bf345f62a7cc2 |
A381455 | Number of multisets that can be obtained by taking the sum of each block of a multiset partition of the prime indices of n into a multiset of constant multisets. | [
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"3",
"2",
"1",
"1",
"2",
"1",
"1",
"1",
"5",
"1",
"2",
"1",
"2",
"1",
"1",
"1",
"3",
"2",
"1",
"3",
"2",
"1",
"1",
"1",
"7",
"1",
"1",
"1",
"4",
"1",
"1",
"1",
"3",
"1",
"1",
"1",
"2",
"2",
"1",
"1",
"5",
"2",
"2",
"1",
"2",
"1",
"3",
"1",
"3",
"1",
"1",
"1",
"2",
"1",
"1",
"2",
"11",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"6",
"1",
"1",
"2",
"2",
"1",
"1",
"1",
"5",
"5",
"1",
"1",
"2",
"1",
"1",
"1"
] | [
"nonn"
] | 19 | 1 | 4 | [
"A000009",
"A000040",
"A000041",
"A000688",
"A000720",
"A001055",
"A001222",
"A002577",
"A002846",
"A003963",
"A005117",
"A006171",
"A018818",
"A045778",
"A050320",
"A050326",
"A050361",
"A055396",
"A056239",
"A061395",
"A112798",
"A122111",
"A213242",
"A213427",
"A265947",
"A275870",
"A279784",
"A289078",
"A293243",
"A295935",
"A299200",
"A299202",
"A300273",
"A300383",
"A300385",
"A317141",
"A321469",
"A381078",
"A381441",
"A381452",
"A381453",
"A381454",
"A381455",
"A381633",
"A381634",
"A381635",
"A381636",
"A381637",
"A381715",
"A381716"
] | null | Gus Wiseman, Mar 06 2025 | 2025-04-01T12:16:27 | oeisdata/seq/A381/A381455.seq | 30c60be23e9308a4b03345e88a88ecaa |
A381456 | Decimal expansion of Product_{p prime} p^(1/(p^2-1)). | [
"1",
"7",
"6",
"8",
"1",
"9",
"8",
"0",
"7",
"8",
"1",
"5",
"3",
"2",
"4",
"4",
"9",
"8",
"4",
"1",
"3",
"0",
"8",
"5",
"3",
"0",
"7",
"7",
"2",
"3",
"1",
"4",
"9",
"6",
"5",
"5",
"2",
"3",
"1",
"2",
"9",
"4",
"2",
"2",
"8",
"5",
"9",
"1",
"2",
"5",
"8",
"9",
"7",
"6",
"1",
"2",
"5",
"3",
"0",
"1",
"4",
"1",
"3",
"7",
"5",
"8",
"6",
"1",
"0",
"7",
"9",
"1",
"4",
"6",
"0",
"0",
"0",
"0",
"4",
"3",
"0",
"0",
"9",
"3",
"0",
"3",
"1",
"5",
"7",
"1",
"7",
"1",
"0",
"7",
"2",
"8",
"5",
"1",
"5",
"6",
"1",
"9",
"3",
"8",
"0",
"6",
"6",
"6"
] | [
"cons",
"nonn",
"changed"
] | 53 | 1 | 2 | [
"A000040",
"A001620",
"A013661",
"A074962",
"A085548",
"A306016",
"A381456",
"A381522",
"A381898"
] | null | Jwalin Bhatt, Feb 24 2025 | 2025-04-28T00:05:12 | oeisdata/seq/A381/A381456.seq | 0b4923c81fcd8ae39e4f2a0e1ad0711f |
A381457 | Integers encoding the recursive structure of a bitonic sorter network of n elements in their binary expansion. | [
"0",
"2",
"5",
"2762",
"22325",
"175338",
"1405781",
"187796017958058",
"12026023042822997",
"768764969792360106",
"49208135664973067605",
"3148398007269257431722",
"201504853864147844281685",
"12895366188400224861219498",
"825310989999256684769531221"
] | [
"nonn",
"base"
] | 51 | 1 | 2 | [
"A000217",
"A001788",
"A381457"
] | null | Darío Clavijo, Mar 13 2025 | 2025-04-01T18:12:49 | oeisdata/seq/A381/A381457.seq | d56bf72ed36f5b7e15cf340b75fe448f |
A381458 | Primes p such that p/prev_prime(p) < 1 + (1/PrimePi(p)). | [
"19",
"31",
"43",
"61",
"73",
"103",
"109",
"139",
"151",
"167",
"181",
"193",
"197",
"199",
"227",
"229",
"233",
"241",
"271",
"281",
"283",
"311",
"313",
"317",
"349",
"353",
"383",
"401",
"421",
"433",
"443",
"461",
"463",
"467",
"491",
"503",
"523",
"571",
"601",
"617",
"619",
"643",
"647",
"661",
"677",
"743",
"761",
"773",
"811",
"823",
"827",
"829",
"857",
"859",
"863",
"881",
"883",
"887",
"911",
"941",
"971"
] | [
"nonn"
] | 52 | 1 | 1 | [
"A000720",
"A151799",
"A381458"
] | null | Alain Rocchelli, Feb 28 2025 | 2025-04-01T20:01:31 | oeisdata/seq/A381/A381458.seq | 7a88516783b3ec9092f28e47f6b311a0 |
A381460 | Smallest n-th perfect power greater than 1 satisfying A373387(a(n)) = n. | [
"2",
"49",
"15625",
"625",
"7737809375",
"735091890625",
"1253790880222890625",
"6634204312890625",
"47312447868976594992787109375",
"72624607478879073313928212890625",
"471781339858152691906169456697218212890625",
"1344888824246298437178134918212890625"
] | [
"nonn",
"base",
"hard"
] | 10 | 1 | 1 | [
"A018247",
"A018248",
"A063006",
"A091661",
"A091663",
"A091664",
"A120817",
"A120818",
"A290372",
"A290373",
"A290374",
"A290375",
"A317905",
"A373387",
"A379243",
"A381460"
] | null | Marco Ripà, Feb 24 2025 | 2025-03-02T23:34:13 | oeisdata/seq/A381/A381460.seq | 5692b62e67f3246ba5dbc17a13f997d9 |
A381461 | Number of permutations of [n] with no fixed points where adjacent elements differ by at least 3. | [
"1",
"0",
"0",
"0",
"0",
"0",
"2",
"8",
"115",
"1274",
"15099",
"179628",
"2260064",
"30534802",
"441269110",
"6789665680",
"110947884520",
"1920180939650",
"35099424286573",
"675866037989156",
"13676799446869485",
"290208293166279344",
"6443880771921767240"
] | [
"nonn",
"more"
] | 25 | 0 | 7 | [
"A000166",
"A002464",
"A127697",
"A288208",
"A381461"
] | null | Alois P. Heinz, Feb 24 2025 | 2025-03-11T15:26:10 | oeisdata/seq/A381/A381461.seq | 3b28a42d88cea80d609a3f33b5c0f6e1 |
A381462 | Limiting sequence of the possible number of inversions in stable configurations of 3^n-1 chips in a chip firing-game directed 3-ary tree resulting from a permutation-based strategy of firing chips | [
"0",
"1",
"3",
"4",
"5",
"9",
"10",
"12",
"13",
"14",
"15",
"16",
"17",
"18",
"27",
"28",
"30",
"31",
"32",
"36",
"37",
"39",
"40",
"41",
"42",
"43",
"44",
"45",
"46",
"48",
"49",
"50",
"51",
"52",
"53",
"54",
"55",
"56",
"57",
"58",
"81",
"82",
"84",
"85",
"86",
"90",
"91",
"93",
"94",
"95",
"96",
"97",
"98",
"99",
"108",
"109",
"111",
"112",
"113",
"117",
"118",
"120",
"121",
"122",
"123",
"124",
"125"
] | [
"nonn"
] | 53 | 1 | 3 | [
"A376116",
"A381462",
"A381463"
] | null | Ryota Inagaki, Tanya Khovanova, and Austin Luo, Feb 24 2025 | 2025-03-25T23:40:16 | oeisdata/seq/A381/A381462.seq | e8c28f24b67d880a69fdcf777a04c093 |
A381463 | Limiting sequence of the possible number of inversions in stable configurations of 4^n-1 chips in a chip firing-game directed 4-ary tree resulting from a permutation-based strategy of firing chips | [
"0",
"1",
"4",
"5",
"6",
"16",
"17",
"20",
"21",
"22",
"24",
"25",
"26",
"27",
"64",
"65",
"68",
"69",
"70",
"80",
"81",
"84",
"85",
"86",
"88",
"89",
"90",
"91",
"96",
"97",
"100",
"101",
"102",
"104",
"105",
"106",
"107",
"108",
"109",
"110",
"111",
"112",
"256",
"257",
"260",
"261",
"262",
"272",
"273",
"276",
"277",
"278",
"280",
"281",
"282",
"283",
"320",
"321",
"324",
"325",
"326",
"336",
"337",
"340"
] | [
"nonn"
] | 33 | 1 | 3 | [
"A376116",
"A381462",
"A381463"
] | null | Ryota Inagaki, Tanya Khovanova, and Austin Luo, Feb 24 2025 | 2025-03-26T08:28:07 | oeisdata/seq/A381/A381463.seq | dca53158311513b5795c17fff5a7a47d |
A381464 | Lexicographically earliest positive integer sequence satisfying a(n) = a(a(n))/n. | [
"1",
"3",
"6",
"5",
"20",
"18",
"8",
"56",
"10",
"90",
"12",
"132",
"14",
"182",
"16",
"240",
"19",
"108",
"323",
"100",
"22",
"462",
"24",
"552",
"26",
"650",
"28",
"756",
"30",
"870",
"32",
"992",
"34",
"1122",
"36",
"1260",
"38",
"1406",
"40",
"1560",
"42",
"1722",
"44",
"1892",
"46",
"2070",
"48",
"2256",
"50",
"2450",
"52",
"2652",
"54",
"2862",
"57",
"448",
"3135",
"59",
"3422",
"61",
"3660",
"63",
"3906",
"65",
"4160"
] | [
"nonn",
"easy"
] | 42 | 1 | 2 | [
"A000045",
"A000304",
"A099267",
"A257794",
"A358793",
"A381464"
] | null | Thomas Scheuerle, Feb 24 2025 | 2025-03-03T13:27:25 | oeisdata/seq/A381/A381464.seq | cb492ce7fa8882e6d2deacf9f38574f6 |
A381465 | Semiprimes k such that 6*k + 1 is also a semiprime. | [
"4",
"9",
"14",
"15",
"22",
"34",
"39",
"49",
"65",
"69",
"74",
"82",
"85",
"86",
"93",
"94",
"111",
"133",
"145",
"158",
"159",
"183",
"185",
"194",
"201",
"203",
"209",
"214",
"219",
"226",
"235",
"259",
"265",
"267",
"289",
"299",
"301",
"303",
"319",
"321",
"323",
"326",
"327",
"334",
"341",
"346",
"358",
"361",
"362",
"365",
"371",
"377",
"386",
"393",
"403",
"407",
"413",
"415",
"422",
"427",
"437",
"469",
"471"
] | [
"nonn"
] | 12 | 1 | 1 | [
"A001358",
"A007693",
"A111153",
"A111170",
"A381465"
] | null | Zak Seidov and Robert Israel, Feb 24 2025 | 2025-02-26T06:28:29 | oeisdata/seq/A381/A381465.seq | 67536663f1bb608882d4a934df25ed99 |
A381466 | a(0) = 4; for n > 0, a(n) = a(n-1) + n if G = 1 or a(n) = n/G if G > 1, where G = gcd(a(n-1), n). | [
"4",
"5",
"7",
"10",
"2",
"7",
"13",
"20",
"2",
"11",
"21",
"32",
"3",
"16",
"7",
"22",
"8",
"25",
"43",
"62",
"10",
"31",
"53",
"76",
"6",
"31",
"57",
"9",
"37",
"66",
"5",
"36",
"8",
"41",
"75",
"7",
"43",
"80",
"19",
"58",
"20",
"61",
"103",
"146",
"22",
"67",
"113",
"160",
"3",
"52",
"25",
"76",
"13",
"66",
"9",
"64",
"7",
"64",
"29",
"88",
"15",
"76",
"31",
"94",
"32",
"97",
"163",
"230",
"34",
"103",
"173",
"244"
] | [
"nonn"
] | 37 | 0 | 1 | [
"A091508",
"A133058",
"A381466"
] | null | Sam Chapman, Feb 24 2025 | 2025-03-02T10:03:34 | oeisdata/seq/A381/A381466.seq | e8bdbcd7eb174cc5b5b1bfe8388edd90 |
A381467 | Triangle read by rows: T(n,k) is the number of simple connected graphs on n unlabeled nodes with k cycles and no node a member of more than one cycle, 0 <= k <= floor(n/3). | [
"1",
"1",
"1",
"1",
"1",
"2",
"2",
"3",
"5",
"6",
"13",
"1",
"11",
"33",
"4",
"23",
"89",
"21",
"47",
"240",
"85",
"2",
"106",
"657",
"345",
"16",
"235",
"1806",
"1289",
"109",
"551",
"5026",
"4713",
"627",
"6",
"1301",
"13999",
"16622",
"3259",
"64",
"3159",
"39260",
"57535",
"15576",
"598",
"7741",
"110381",
"195212",
"69983",
"4394",
"18",
"19320",
"311465",
"653318",
"299354",
"28286",
"295"
] | [
"nonn",
"tabf"
] | 16 | 0 | 6 | [
"A000055",
"A001429",
"A380631",
"A380634",
"A381467",
"A381468",
"A381470"
] | null | Andrew Howroyd, Feb 24 2025 | 2025-02-25T13:13:38 | oeisdata/seq/A381/A381467.seq | ac18195db1d6b1d7d02ce98f74e09901 |
A381468 | Number of simple connected graphs on n unlabeled nodes with no node a member of more than one cycle. | [
"1",
"1",
"1",
"2",
"4",
"8",
"20",
"48",
"133",
"374",
"1124",
"3439",
"10923",
"35245",
"116128",
"387729",
"1312038",
"4485906",
"15486546",
"53900520",
"188998450",
"667062919",
"2368440477",
"8454560144",
"30328595227",
"109285433191",
"395425965732",
"1436219868659",
"5234881134074",
"19143123415166",
"70216752517419"
] | [
"nonn"
] | 8 | 0 | 4 | [
"A000083",
"A317722",
"A380632",
"A380805",
"A381467",
"A381468"
] | null | Andrew Howroyd, Feb 24 2025 | 2025-02-25T01:57:14 | oeisdata/seq/A381/A381468.seq | 9854d521614e143f31b88c44af6467b7 |
A381469 | Number of unlabeled 2,3 cacti (triangular cacti with bridges) rooted at a triangle with n triangles and every node contained in exactly one triangle. | [
"0",
"1",
"1",
"4",
"15",
"66",
"304",
"1503",
"7622",
"39856",
"212447",
"1151614",
"6324924",
"35127396",
"196917025",
"1112776860",
"6332114208",
"36252066562",
"208665030299",
"1206819559836",
"7009605269315",
"40871341270810",
"239144296550695",
"1403719120877546",
"8263431521645830",
"48774908707685849"
] | [
"nonn"
] | 7 | 0 | 4 | [
"A287891",
"A380634",
"A381469"
] | null | Andrew Howroyd, Feb 25 2025 | 2025-02-25T01:57:28 | oeisdata/seq/A381/A381469.seq | dbdc64251bb35f39804a28d600bb3df4 |
A381470 | Number of simple connected graphs on n unlabeled nodes with exactly 2 non-overlapping cycles. | [
"1",
"4",
"21",
"85",
"345",
"1289",
"4713",
"16622",
"57535",
"195212",
"653318",
"2158866",
"7063333",
"22906699",
"73742762",
"235863378",
"750187968",
"2374249283",
"7481414941",
"23482536967",
"73449564533",
"229016163367",
"712044375528",
"2208131225648",
"6831543467752",
"21089958138852",
"64978894444220"
] | [
"nonn"
] | 6 | 6 | 2 | [
"A000081",
"A000083",
"A001429",
"A381467",
"A381470"
] | null | Andrew Howroyd, Feb 25 2025 | 2025-02-25T11:37:39 | oeisdata/seq/A381/A381470.seq | 297da1038ccac5a19d9c9314d80280b2 |
A381471 | Number of non-isomorphic Dynkin systems on n points. | [
"1",
"1",
"2",
"3",
"7",
"13",
"63",
"838"
] | [
"nonn",
"more"
] | 7 | 0 | 3 | [
"A000041",
"A380571",
"A381471"
] | null | Andrew Howroyd, Feb 26 2025 | 2025-03-05T15:08:17 | oeisdata/seq/A381/A381471.seq | 4442ce62c1bbdf34f249594d0c09ce22 |
A381472 | Number of unlabeled set systems on n vertices which are closed under union of disjoint sets. | [
"1",
"2",
"5",
"22",
"345",
"152589"
] | [
"nonn",
"hard",
"more"
] | 6 | 0 | 2 | [
"A000612",
"A193674",
"A381471",
"A381472",
"A381575"
] | null | Andrew Howroyd, Mar 02 2025 | 2025-03-05T15:08:12 | oeisdata/seq/A381/A381472.seq | 1a4286f1ddd49de27d93f5da7980709a |
A381473 | Decimal expansion of the smallest positive solution to 2*x = tan(x). | [
"1",
"1",
"6",
"5",
"5",
"6",
"1",
"1",
"8",
"5",
"2",
"0",
"7",
"2",
"1",
"1",
"3",
"0",
"6",
"8",
"3",
"3",
"9",
"1",
"7",
"9",
"7",
"7",
"9",
"5",
"8",
"5",
"6",
"0",
"6",
"6",
"9",
"1",
"3",
"4",
"5",
"3",
"8",
"8",
"4",
"7",
"6",
"9",
"3",
"0",
"5",
"7",
"2",
"8",
"7",
"5",
"5",
"4",
"8",
"6",
"8",
"6",
"4",
"6",
"6",
"9",
"6",
"6",
"1",
"5",
"4",
"0",
"8",
"7",
"1",
"6",
"3",
"5",
"8",
"3",
"3",
"6",
"9",
"2",
"1",
"0",
"7",
"7",
"1",
"2",
"8",
"5",
"5",
"2",
"1",
"9",
"6",
"5",
"0",
"7",
"0",
"4",
"3",
"7",
"2",
"9",
"6",
"7"
] | [
"nonn",
"cons"
] | 7 | 1 | 3 | [
"A257451",
"A381473"
] | null | Andrew Howroyd, Mar 10 2025 | 2025-03-10T19:55:54 | oeisdata/seq/A381/A381473.seq | 139c66aa51c3770ff1c30e2339c053eb |
A381474 | Array read by antidiagonals: T(m,n) is the number of minimum connected dominating sets in the grid graph P_m X P_n. | [
"1",
"2",
"2",
"1",
"4",
"1",
"1",
"1",
"1",
"1",
"1",
"7",
"2",
"7",
"1",
"1",
"8",
"1",
"1",
"8",
"1",
"1",
"8",
"1",
"16",
"1",
"8",
"1",
"1",
"8",
"1",
"62",
"62",
"1",
"8",
"1",
"1",
"8",
"1",
"10",
"126",
"10",
"1",
"8",
"1",
"1",
"8",
"1",
"48",
"11",
"11",
"48",
"1",
"8",
"1",
"1",
"8",
"1",
"224",
"448",
"24",
"448",
"224",
"1",
"8",
"1",
"1",
"8",
"1",
"8",
"744",
"13",
"13",
"744",
"8",
"1",
"8",
"1"
] | [
"nonn",
"tabl"
] | 9 | 1 | 2 | [
"A291872",
"A350820",
"A381474",
"A381475",
"A381730"
] | null | Andrew Howroyd, Mar 19 2025 | 2025-03-19T18:41:40 | oeisdata/seq/A381/A381474.seq | 5b8f13a65398ca69a557143dfb5b24ae |
A381475 | Array read by antidiagonals: T(m,n) is the connected domination number of the grid graph P_m X P_n. | [
"1",
"1",
"1",
"1",
"2",
"1",
"2",
"2",
"2",
"2",
"3",
"4",
"3",
"4",
"3",
"4",
"5",
"4",
"4",
"5",
"4",
"5",
"6",
"5",
"7",
"5",
"6",
"5",
"6",
"7",
"6",
"9",
"9",
"6",
"7",
"6",
"7",
"8",
"7",
"10",
"11",
"10",
"7",
"8",
"7",
"8",
"9",
"8",
"12",
"12",
"12",
"12",
"8",
"9",
"8",
"9",
"10",
"9",
"14",
"15",
"14",
"15",
"14",
"9",
"10",
"9",
"10",
"11",
"10",
"15",
"17",
"16",
"16",
"17",
"15",
"10",
"11",
"10"
] | [
"nonn",
"tabl"
] | 6 | 1 | 5 | [
"A300358",
"A350823",
"A369692",
"A381474",
"A381475"
] | null | Andrew Howroyd, Mar 19 2025 | 2025-03-19T18:42:37 | oeisdata/seq/A381/A381475.seq | 95f1f4a57c650adaa562a8298ff84e11 |
A381476 | Triangle read by rows: T(n,k) is the number of subsets of {1..n} with k elements such that every pair of distinct elements has a different difference, 0 <= k <= A143824(n). | [
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"3",
"3",
"1",
"4",
"6",
"2",
"1",
"5",
"10",
"6",
"1",
"6",
"15",
"14",
"1",
"7",
"21",
"26",
"2",
"1",
"8",
"28",
"44",
"10",
"1",
"9",
"36",
"68",
"26",
"1",
"10",
"45",
"100",
"60",
"1",
"11",
"55",
"140",
"110",
"1",
"12",
"66",
"190",
"190",
"4",
"1",
"13",
"78",
"250",
"304",
"22",
"1",
"14",
"91",
"322",
"466",
"68",
"1",
"15",
"105",
"406",
"676",
"156"
] | [
"nonn",
"tabf"
] | 9 | 0 | 5 | [
"A000012",
"A001477",
"A003022",
"A143823",
"A143824",
"A161680",
"A212964",
"A241688",
"A241689",
"A241690",
"A325879",
"A381476",
"A382395"
] | null | Andrew Howroyd, Mar 27 2025 | 2025-03-27T21:31:40 | oeisdata/seq/A381/A381476.seq | 3994b4eda55ed1177eff383a3fb50045 |
A381477 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x)^2 * cosh(x * A(x)^2) ). | [
"1",
"1",
"6",
"75",
"1440",
"37445",
"1231440",
"49037527",
"2294425728",
"123393443049",
"7500623201280",
"508577491719011",
"38057966976387072",
"3115680296111519149",
"277005128553759191040",
"26579020362900758232495",
"2737628961211699538657280",
"301278578823933606439917137",
"35281158151116225085977526272"
] | [
"nonn"
] | 8 | 0 | 3 | [
"A185951",
"A364985",
"A381386",
"A381477"
] | null | Seiichi Manyama, Feb 24 2025 | 2025-02-25T06:43:56 | oeisdata/seq/A381/A381477.seq | 78117df799414045a8a4f884fa715dfe |
A381478 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x) * cosh(x * A(x)) )^2. | [
"1",
"2",
"14",
"186",
"3696",
"98290",
"3283920",
"132311354",
"6246905728",
"338374946466",
"20688891816960",
"1409607482926522",
"105914955915952128",
"8701156803022552466",
"775923181679913938944",
"74646655589398509637050",
"7706371729268071660093440",
"849834260414107910987980354"
] | [
"nonn"
] | 12 | 0 | 2 | [
"A185951",
"A377546",
"A381387",
"A381449",
"A381477",
"A381478"
] | null | Seiichi Manyama, Feb 24 2025 | 2025-02-25T01:58:01 | oeisdata/seq/A381/A381478.seq | 0b4b62822ab75916f46734cea2b75275 |
A381479 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x)^2 * cos(x * A(x)^2) ). | [
"1",
"1",
"6",
"69",
"1200",
"28085",
"828240",
"29502473",
"1232606592",
"59114482569",
"3201204188160",
"193215861134989",
"12862437022076928",
"936256855741871677",
"73978404781917941760",
"6306254322850544942865",
"576881179288397985054720",
"56369243043268551691136657",
"5859726074013471622734938112"
] | [
"nonn"
] | 8 | 0 | 3 | [
"A185951",
"A364985",
"A381388",
"A381479"
] | null | Seiichi Manyama, Feb 24 2025 | 2025-02-25T01:58:36 | oeisdata/seq/A381/A381479.seq | 9eb8f0c7181392dcd07724e12e5fcb37 |
A381480 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x) * cos(x * A(x)) )^2. | [
"1",
"2",
"14",
"174",
"3168",
"76450",
"2304720",
"83473726",
"3533382272",
"171254814210",
"9355068840960",
"568799458870478",
"38102773549750272",
"2788540163472852386",
"221380225364522119168",
"18950242574522637197790",
"1739955233454599038402560",
"170582215179135413189856514",
"17785491645892269582026145792"
] | [
"nonn"
] | 10 | 0 | 2 | [
"A185951",
"A381478",
"A381480"
] | null | Seiichi Manyama, Feb 24 2025 | 2025-02-25T01:59:05 | oeisdata/seq/A381/A381480.seq | ddf5b824006a2d3e61e84f30374e36af |
A381481 | Dirichlet g.f.: zeta(s) * Product_{p prime} (1 - 1/p^(2*s) - 1/p^(3*s)). | [
"1",
"1",
"1",
"0",
"1",
"1",
"1",
"-1",
"0",
"1",
"1",
"0",
"1",
"1",
"1",
"-1",
"1",
"0",
"1",
"0",
"1",
"1",
"1",
"-1",
"0",
"1",
"-1",
"0",
"1",
"1",
"1",
"-1",
"1",
"1",
"1",
"0",
"1",
"1",
"1",
"-1",
"1",
"1",
"1",
"0",
"0",
"1",
"1",
"-1",
"0",
"0",
"1",
"0",
"1",
"-1",
"1",
"-1",
"1",
"1",
"1",
"0",
"1",
"1",
"0",
"-1",
"1",
"1",
"1",
"0",
"1",
"1",
"1",
"0",
"1",
"1",
"0",
"0",
"1",
"1",
"1",
"-1",
"-1",
"1",
"1",
"0",
"1",
"1",
"1",
"-1",
"1",
"0",
"1",
"0",
"1",
"1",
"1",
"-1",
"1",
"0",
"0",
"0"
] | [
"sign",
"mult",
"easy",
"new"
] | 22 | 1 | null | [
"A013661",
"A065470",
"A299406",
"A365498",
"A380922",
"A381481",
"A383292"
] | null | Vaclav Kotesovec, Apr 22 2025 | 2025-04-22T11:06:58 | oeisdata/seq/A381/A381481.seq | b160a9b366669ec6ede6ae157214077d |
A381482 | a(n) = Sum_{k=0..floor(n/2)} binomial(n,k)^2 * binomial(n-k,k) * 2^k. | [
"1",
"1",
"9",
"37",
"241",
"1401",
"8961",
"57429",
"377217",
"2509201",
"16876729",
"114600069",
"783903121",
"5397915433",
"37372017489",
"259998843477",
"1816376953857",
"12736545070113",
"89602978644969",
"632223913939557",
"4472680961409201",
"31717890254271321",
"225416254500886689",
"1605197563027768917"
] | [
"nonn",
"new"
] | 12 | 0 | 3 | [
"A001045",
"A001850",
"A084601",
"A206178",
"A275027",
"A381482"
] | null | Ilya Gutkovskiy, Apr 22 2025 | 2025-04-23T10:55:22 | oeisdata/seq/A381/A381482.seq | 0e9b0a71040a6b09886d168e6a8714e8 |
A381484 | Expansion of e.g.f. exp(-x/3) / (1-3*x)^(1/9). | [
"1",
"0",
"1",
"6",
"57",
"708",
"10905",
"200538",
"4287633",
"104507496",
"2860291089",
"86853807630",
"2897638853769",
"105357244427244",
"4146601837761513",
"175632278607964962",
"7965651564924845985",
"385161391574120046672",
"19778647046883844762017",
"1074979845580061777989014"
] | [
"nonn",
"new"
] | 29 | 0 | 4 | [
"A000166",
"A381484",
"A381504",
"A383313"
] | null | Seiichi Manyama, Apr 23 2025 | 2025-04-23T10:19:45 | oeisdata/seq/A381/A381484.seq | ce3ac40a8e5d988bdc009b85320191c6 |
A381485 | Decimal expansion of sqrt(13)/6. | [
"6",
"0",
"0",
"9",
"2",
"5",
"2",
"1",
"2",
"5",
"7",
"7",
"3",
"3",
"1",
"5",
"4",
"8",
"8",
"5",
"3",
"2",
"0",
"3",
"5",
"4",
"4",
"5",
"7",
"8",
"4",
"1",
"5",
"9",
"9",
"1",
"0",
"4",
"1",
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"2",
"7",
"6",
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"1",
"0",
"3",
"5",
"4",
"5",
"1",
"7",
"4",
"2",
"1",
"7",
"6",
"0",
"3",
"7",
"8",
"6",
"1",
"1",
"5",
"8",
"0",
"4",
"8",
"8",
"3",
"5",
"0",
"7",
"4",
"2",
"0",
"0",
"7",
"6",
"9",
"8",
"4",
"7",
"0",
"0",
"3",
"0",
"8",
"1",
"7",
"8",
"6",
"2",
"7",
"8",
"9",
"1",
"9"
] | [
"nonn",
"cons",
"easy"
] | 5 | 0 | 1 | [
"A002193",
"A010470",
"A010503",
"A020761",
"A101263",
"A120683",
"A142464",
"A176019",
"A281065",
"A295330",
"A344069",
"A379338",
"A381485"
] | null | Amiram Eldar, Feb 24 2025 | 2025-02-25T02:29:54 | oeisdata/seq/A381/A381485.seq | bcb319e6749a7f88d655713e03e06a8d |
A381486 | Number of labeled histories for rooted ternary trees with 2n+1 leaves if simultaneous trifurcations are allowed. | [
"1",
"1",
"10",
"420",
"43960",
"9347800",
"3513910400",
"2131249120000",
"1952028782704000",
"2568150610833808000",
"4666919676058159520000",
"11351087418588355518080000",
"36008099327884173922432000000",
"145785514242304854141480256000000",
"739598808823839440680777500928000000",
"4627885522642342503645368137231360000000"
] | [
"nonn"
] | 15 | 0 | 3 | [
"A317059",
"A339411",
"A381486"
] | null | Noah A Rosenberg, Feb 25 2025 | 2025-02-26T09:51:30 | oeisdata/seq/A381/A381486.seq | fd6917f7d802d12f0c353f73a268a144 |
A381487 | Numbers which are a power of their digital root. | [
"0",
"1",
"2",
"3",
"4",
"5",
"6",
"7",
"8",
"9",
"81",
"128",
"256",
"512",
"729",
"2401",
"6561",
"8192",
"16384",
"32768",
"59049",
"78125",
"524288",
"531441",
"823543",
"1048576",
"2097152",
"4782969",
"33554432",
"43046721",
"67108864",
"134217728",
"282475249",
"387420489",
"1220703125",
"2147483648",
"3486784401",
"4294967296"
] | [
"nonn",
"base"
] | 26 | 1 | 3 | [
"A000012",
"A010689",
"A010734",
"A010888",
"A023106",
"A070366",
"A070403",
"A100401",
"A100402",
"A100403",
"A153130",
"A381487",
"A381491",
"A381492"
] | null | Stefano Spezia, Feb 25 2025 | 2025-02-27T07:12:07 | oeisdata/seq/A381/A381487.seq | 9c48c1358bc5a59e6405592bb268034d |
A381488 | Pentagonal numbers that are deficient. | [
"1",
"5",
"22",
"35",
"51",
"92",
"117",
"145",
"247",
"287",
"376",
"425",
"477",
"590",
"651",
"715",
"782",
"925",
"1001",
"1162",
"1247",
"1335",
"1426",
"1617",
"1717",
"2035",
"2147",
"2501",
"2625",
"2882",
"3015",
"3151",
"3577",
"3725",
"4187",
"4347",
"4845",
"5017",
"5551",
"5735",
"6112",
"6305",
"6501",
"6902",
"7107",
"7315",
"7526",
"7957"
] | [
"nonn"
] | 20 | 1 | 2 | [
"A000326",
"A005100",
"A379264",
"A381488"
] | null | Massimo Kofler, Feb 25 2025 | 2025-03-03T12:42:52 | oeisdata/seq/A381/A381488.seq | 32d4a887e1506d07741cda82541f432b |
A381489 | Index of first half of decomposition of integers into pairs x(i)+y(j) based on A380008 and A380009, respectively. | [
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7",
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7",
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"0",
"0",
"1",
"1",
"2",
"2",
"3",
"3",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7",
"4",
"4",
"5",
"5",
"6",
"6",
"7",
"7"
] | [
"easy",
"nonn"
] | 22 | 0 | 5 | [
"A380008",
"A380009",
"A381489",
"A381490"
] | null | Luis Rato, Feb 25 2025 | 2025-03-21T02:24:18 | oeisdata/seq/A381/A381489.seq | 29591f9d6d73ed8072123c9fa68896cb |
A381490 | Index of second half of decomposition of integers into pairs x(i)+y(j) based on A380008 and A380009, respectively. | [
"0",
"1",
"0",
"1",
"0",
"1",
"0",
"1",
"2",
"3",
"2",
"3",
"2",
"3",
"2",
"3",
"0",
"1",
"0",
"1",
"0",
"1",
"0",
"1",
"2",
"3",
"2",
"3",
"2",
"3",
"2",
"3",
"4",
"5",
"4",
"5",
"4",
"5",
"4",
"5",
"6",
"7",
"6",
"7",
"6",
"7",
"6",
"7",
"4",
"5",
"4",
"5",
"4",
"5",
"4",
"5",
"6",
"7",
"6",
"7",
"6",
"7",
"6",
"7",
"8",
"9",
"8",
"9",
"8",
"9",
"8",
"9",
"10",
"11",
"10",
"11",
"10",
"11",
"10",
"11",
"8",
"9",
"8",
"9",
"8",
"9",
"8",
"9"
] | [
"easy",
"nonn"
] | 15 | 0 | 9 | [
"A380008",
"A380009",
"A381489",
"A381490"
] | null | Luis Rato, Feb 25 2025 | 2025-03-06T14:45:34 | oeisdata/seq/A381/A381490.seq | 07e81cb80ec5804132e96eead6f0c3ba |
A381491 | a(n) = A010888(A381487(n)). | [
"0",
"1",
"2",
"3",
"4",
"5",
"6",
"7",
"8",
"9",
"9",
"2",
"4",
"8",
"9",
"7",
"9",
"2",
"4",
"8",
"9",
"5",
"2",
"9",
"7",
"4",
"8",
"9",
"2",
"9",
"4",
"8",
"7",
"9",
"5",
"2",
"9",
"4",
"8",
"9",
"7",
"2",
"4",
"9",
"8",
"9",
"2",
"4",
"5",
"9",
"7",
"8",
"9",
"2",
"4",
"9",
"8",
"7",
"9",
"2",
"4",
"8",
"9",
"5",
"9",
"2",
"7",
"4",
"8",
"9",
"9",
"2",
"4",
"8",
"9",
"7",
"5",
"9",
"2",
"4",
"8",
"9",
"7",
"2",
"9",
"4",
"8",
"9"
] | [
"nonn",
"base"
] | 17 | 1 | 3 | [
"A010888",
"A381487",
"A381491",
"A381492"
] | null | Stefano Spezia, Feb 25 2025 | 2025-02-27T10:48:48 | oeisdata/seq/A381/A381491.seq | 65959eb8648122b2cf833712326bdce8 |
A381492 | a(n) is the logarithm to base A381491(n) of A381487(n). | [
"0",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"7",
"4",
"3",
"3",
"4",
"4",
"13",
"7",
"5",
"5",
"7",
"19",
"6",
"7",
"10",
"7",
"7",
"25",
"8",
"13",
"9",
"10",
"9",
"13",
"31",
"10",
"16",
"11",
"11",
"13",
"37",
"19",
"12",
"13",
"13",
"43",
"22",
"19",
"14",
"16",
"15",
"15",
"49",
"25",
"16",
"17",
"19",
"17",
"55",
"28",
"19",
"18",
"25",
"19",
"61",
"22",
"31",
"21",
"20",
"21",
"67",
"34",
"23",
"22",
"25"
] | [
"nonn",
"base"
] | 16 | 1 | 11 | [
"A381487",
"A381491",
"A381492"
] | null | Stefano Spezia, Feb 25 2025 | 2025-02-27T10:48:03 | oeisdata/seq/A381/A381492.seq | 6a26c8a7d7c021f0f4c065886c6cceaf |
A381493 | Smallest number with reciprocal of period length n in base 8. | [
"1",
"7",
"3",
"73",
"5",
"31",
"19",
"49",
"17",
"262657",
"11",
"23",
"37",
"79",
"43",
"631",
"97",
"103",
"81",
"32377",
"25",
"3577",
"67",
"47",
"323",
"601",
"237",
"2593",
"29",
"233",
"209",
"2147483647",
"193",
"199",
"307",
"71",
"405",
"223",
"571",
"937",
"187",
"13367",
"817",
"431",
"115",
"271",
"139",
"2351",
"577",
"343",
"251"
] | [
"nonn",
"base"
] | 15 | 0 | 2 | [
"A003060",
"A379641",
"A381493"
] | null | Erich Friedman, Feb 25 2025 | 2025-02-28T15:13:53 | oeisdata/seq/A381/A381493.seq | 819d64317ef09cf2be504f0a4ecb0b9c |
A381494 | Smallest number with reciprocal of period length n in base 7. | [
"1",
"2",
"4",
"9",
"5",
"2801",
"36",
"29",
"64",
"27",
"11",
"1123",
"13",
"16148168401",
"113",
"31",
"17",
"14009",
"108",
"419",
"55",
"261",
"23",
"47",
"73",
"2551",
"53",
"81",
"145",
"59",
"99",
"311",
"256",
"3631",
"56036",
"81229",
"135",
"223",
"1676",
"486643",
"41",
"83",
"1017",
"166003607842448777",
"115",
"837",
"188",
"13722816749522711",
"153",
"3529",
"10204"
] | [
"nonn",
"base"
] | 17 | 0 | 2 | [
"A003060",
"A379640",
"A381494"
] | null | Erich Friedman, Feb 25 2025 | 2025-03-03T09:32:16 | oeisdata/seq/A381/A381494.seq | 91c3a2982b01bfdac68360b1bd4620b9 |
A381495 | a(n) is the number of times n appears in A381466. | [
"0",
"2",
"2",
"1",
"3",
"1",
"5",
"2",
"3",
"2",
"2",
"0",
"2",
"0",
"2",
"1",
"0",
"1",
"4",
"2",
"3",
"2",
"3",
"1",
"6",
"0",
"1",
"0",
"4",
"0",
"5",
"2",
"0",
"1",
"0",
"1",
"6",
"0",
"4",
"1",
"3",
"2",
"3",
"1",
"1",
"0",
"2",
"1",
"0",
"0",
"2",
"2",
"4",
"1",
"3",
"0",
"4",
"1",
"4",
"1",
"4",
"1",
"1",
"3",
"1",
"4",
"2",
"0",
"1",
"1",
"2",
"1",
"3",
"0",
"2",
"3",
"3",
"1",
"2",
"3",
"1",
"1",
"2",
"1",
"0",
"0",
"2",
"1",
"1",
"2",
"4",
"0",
"0",
"2",
"1",
"0",
"3",
"0",
"2",
"1",
"2",
"1",
"2",
"0",
"0",
"0",
"3",
"2",
"3",
"0",
"3",
"1",
"3",
"1",
"1",
"2",
"4",
"1",
"3",
"1",
"3",
"0",
"1",
"0",
"2",
"1",
"4",
"1",
"1",
"1"
] | [
"nonn"
] | 19 | 1 | 2 | [
"A381466",
"A381495",
"A381501"
] | null | Sam Chapman, Feb 25 2025 | 2025-03-09T16:40:21 | oeisdata/seq/A381/A381495.seq | 35beb6fd309d031a5c42f05f8996a2d6 |
A381496 | Number of powerful numbers that are not prime powers that do not exceed 10^n. | [
"0",
"0",
"3",
"28",
"133",
"510",
"1790",
"5997",
"19639",
"63541",
"204037",
"652173",
"2078320",
"6609816",
"20993381",
"66612867",
"211222374",
"669428537",
"2120835892",
"6717184256",
"21270247404",
"67341572823",
"213173925948",
"674739560651",
"2135491756895",
"6758117426102",
"21385762133815",
"67670426242420"
] | [
"nonn"
] | 23 | 0 | 3 | [
"A001694",
"A118896",
"A126706",
"A246547",
"A267574",
"A286708",
"A380430",
"A380431",
"A381391",
"A381496"
] | null | Michael De Vlieger, Feb 25 2025 | 2025-04-02T03:05:25 | oeisdata/seq/A381/A381496.seq | d57dffe4b28f56a4449efe9618a4a9ae |
A381497 | a(n) = sum of numbers k < n such that 1 < gcd(k,n) and rad(k) != rad(n), where rad = A007947. | [
"0",
"0",
"0",
"0",
"0",
"9",
"0",
"6",
"6",
"25",
"0",
"36",
"0",
"49",
"45",
"42",
"0",
"81",
"0",
"100",
"84",
"121",
"0",
"144",
"45",
"169",
"96",
"196",
"0",
"315",
"0",
"210",
"198",
"289",
"175",
"354",
"0",
"361",
"273",
"430",
"0",
"609",
"0",
"484",
"435",
"529",
"0",
"648",
"140",
"655",
"459",
"676",
"0",
"801",
"385",
"826",
"570",
"841",
"0",
"1260",
"0",
"961",
"798"
] | [
"nonn"
] | 11 | 1 | 6 | [
"A007947",
"A038566",
"A066760",
"A067392",
"A121998",
"A369609",
"A381094",
"A381096",
"A381497",
"A381498",
"A381499"
] | null | Michael De Vlieger, Mar 02 2025 | 2025-03-07T09:07:10 | oeisdata/seq/A381/A381497.seq | ff9a156e53245fc6e204e89070e8c3b4 |
A381498 | a(n) = sum of numbers k <= n that have the same squarefree kernel as n. | [
"1",
"2",
"3",
"6",
"5",
"6",
"7",
"14",
"12",
"10",
"11",
"18",
"13",
"14",
"15",
"30",
"17",
"36",
"19",
"30",
"21",
"22",
"23",
"60",
"30",
"26",
"39",
"42",
"29",
"30",
"31",
"62",
"33",
"34",
"35",
"96",
"37",
"38",
"39",
"70",
"41",
"42",
"43",
"66",
"60",
"46",
"47",
"144",
"56",
"120",
"51",
"78",
"53",
"198",
"55",
"98",
"57",
"58",
"59",
"90",
"61",
"62",
"84",
"126",
"65",
"66"
] | [
"nonn"
] | 7 | 1 | 2 | [
"A007947",
"A008479",
"A244974",
"A369609",
"A381498"
] | null | Michael De Vlieger, Mar 03 2025 | 2025-03-07T09:07:23 | oeisdata/seq/A381/A381498.seq | 66ee8178420f3b8094e9b1a89fed7627 |
A381499 | a(n) = sum of numbers k < n such that 1 < gcd(k,n) < k and rad(k) does not divide n, where rad = A007947. | [
"0",
"0",
"0",
"0",
"0",
"0",
"0",
"6",
"6",
"6",
"0",
"10",
"0",
"28",
"28",
"42",
"0",
"39",
"0",
"65",
"65",
"80",
"0",
"102",
"45",
"126",
"96",
"159",
"0",
"111",
"0",
"210",
"148",
"210",
"138",
"253",
"0",
"280",
"221",
"338",
"0",
"342",
"0",
"411",
"366",
"444",
"0",
"547",
"140",
"563",
"403",
"601",
"0",
"700",
"344",
"708",
"512",
"750",
"0",
"751",
"0",
"868",
"703",
"930"
] | [
"nonn"
] | 7 | 1 | 8 | [
"A007947",
"A038566",
"A066760",
"A121998",
"A243823",
"A272619",
"A381497",
"A381499"
] | null | Michael De Vlieger, Mar 02 2025 | 2025-03-07T09:07:33 | oeisdata/seq/A381/A381499.seq | b65c6f79de3fa6af1e320fd53888bf22 |
A381500 | a(n) = A019565(A187769(n)). | [
"1",
"2",
"3",
"6",
"5",
"10",
"15",
"30",
"7",
"14",
"21",
"35",
"42",
"70",
"105",
"210",
"11",
"22",
"33",
"55",
"77",
"66",
"110",
"165",
"154",
"231",
"385",
"330",
"462",
"770",
"1155",
"2310",
"13",
"26",
"39",
"65",
"91",
"143",
"78",
"130",
"195",
"182",
"273",
"455",
"286",
"429",
"715",
"1001",
"390",
"546",
"910",
"1365",
"858",
"1430",
"2145",
"2002",
"3003"
] | [
"nonn",
"base",
"easy"
] | 17 | 0 | 2 | [
"A002110",
"A019565",
"A098012",
"A119416",
"A163866",
"A187769",
"A253550",
"A294648",
"A344085",
"A381500"
] | null | Michael De Vlieger, Peter Munn, and Antti Karttunen, Feb 27 2025 | 2025-03-07T11:34:17 | oeisdata/seq/A381/A381500.seq | 25bac0aa4b7ffb6f0e110ea442fcb321 |
A381501 | Positive integers that do not appear in A381466. | [
"1",
"12",
"14",
"17",
"26",
"28",
"30",
"33",
"35",
"38",
"46",
"49",
"50",
"56",
"68",
"74",
"85",
"86",
"92",
"93",
"96",
"98",
"104",
"105",
"106",
"110",
"122",
"124",
"132",
"134",
"140",
"156",
"164",
"166",
"170",
"182",
"188",
"190",
"194",
"195",
"200",
"202",
"214",
"218",
"226",
"236",
"242",
"248",
"250",
"254",
"260",
"284",
"285",
"290",
"302",
"304",
"305",
"308",
"310",
"314",
"320",
"326",
"336",
"338",
"344",
"346",
"350",
"362",
"368",
"374",
"375"
] | [
"nonn"
] | 25 | 1 | 2 | [
"A381466",
"A381495",
"A381501"
] | null | Sam Chapman, Feb 25 2025 | 2025-03-20T04:35:24 | oeisdata/seq/A381/A381501.seq | 25cc0e5ad61bd3684b0f44a9069a2ad7 |
A381502 | a(n) is the smallest number k such that with x(1) = k and x(i+1) = 2*x(i) + 1, x(i+1) has exactly one more prime factor (counted with multiplicity) than x(i) for i = 1 to n but not i = n + 1. | [
"2",
"1",
"87",
"43",
"197161",
"8651161"
] | [
"nonn",
"more"
] | 10 | 1 | 1 | [
"A001222",
"A381502"
] | null | Robert Israel, Feb 25 2025 | 2025-02-27T07:58:20 | oeisdata/seq/A381/A381502.seq | 2f221753bef1177add148c76d42ba3ce |
A381503 | Number of rectangles in a Fibonacci(n) X Fibonacci(n+1) grid. | [
"1",
"3",
"18",
"90",
"540",
"3276",
"21021",
"137445",
"916300",
"6167700",
"41812200",
"284604840",
"1942428033",
"13278352815",
"90862598190",
"622150990734",
"4261620339460",
"29198279495220",
"200080147593645",
"1371167039301345",
"9397260307853496",
"64406143791454248",
"441430873666787088",
"3025546968019741200"
] | [
"nonn",
"easy"
] | 18 | 1 | 2 | [
"A000045",
"A033192",
"A096948",
"A377704",
"A381503"
] | null | Darío Clavijo, Feb 25 2025 | 2025-03-14T21:19:30 | oeisdata/seq/A381/A381503.seq | 4a612ae3a96d4d5fd1f2ab3be2e6405d |
A381504 | Expansion of e.g.f. exp(-x/4) / (1-4*x)^(1/16). | [
"1",
"0",
"1",
"8",
"99",
"1616",
"32815",
"797256",
"22552873",
"728069984",
"26413495281",
"1063820511080",
"47098650935611",
"2273501091042288",
"118834339196361919",
"6686552010270859496",
"402975635704196998545",
"25897425517232941658816",
"1767875520978811381774753",
"127753191169784612437640904"
] | [
"nonn",
"new"
] | 15 | 0 | 4 | [
"A000166",
"A381484",
"A381504",
"A383313"
] | null | Seiichi Manyama, Apr 23 2025 | 2025-04-23T10:17:25 | oeisdata/seq/A381/A381504.seq | d54002f3386e0f13e6fa493abf4caa2e |
A381505 | Expansion of e.g.f. exp(2*x/3) / (1-3*x)^(1/9). | [
"1",
"1",
"2",
"10",
"88",
"1064",
"16144",
"293968",
"6241280",
"151328512",
"4124855296",
"124843943936",
"4153947277312",
"150699794606080",
"5919989155033088",
"250339939417452544",
"11338037538551824384",
"547552961327680913408",
"28087260712728645468160",
"1525087432592278987866112"
] | [
"nonn",
"new"
] | 13 | 0 | 3 | [
"A002801",
"A381505",
"A381506"
] | null | Seiichi Manyama, Apr 23 2025 | 2025-04-23T10:14:45 | oeisdata/seq/A381/A381505.seq | 093c98217e0af907609b40f89369dc06 |
A381506 | Expansion of e.g.f. exp(3*x/4) / (1-4*x)^(1/16). | [
"1",
"1",
"2",
"12",
"138",
"2202",
"44172",
"1064664",
"29947644",
"962720316",
"34812065304",
"1398413067984",
"61779789904248",
"2976866834860728",
"155364530441352912",
"8730749828092965408",
"525584335643810008848",
"33743905825099188235536",
"2301524700814009677800736"
] | [
"nonn",
"new"
] | 13 | 0 | 3 | [
"A002801",
"A381505",
"A381506"
] | null | Seiichi Manyama, Apr 23 2025 | 2025-04-23T10:12:13 | oeisdata/seq/A381/A381506.seq | b8e9b7231168d5dd0fbfed3d2caade78 |
A381507 | Squarefree numbers k such that the sum of 1/(p-1) over the prime divisors p of k is 1. | [
"2",
"1365",
"73815",
"6702045",
"8788065",
"26241285",
"32426205",
"237539445",
"269409855",
"445317015",
"475231515",
"709296105",
"1085962395",
"1329722835",
"1447857915",
"2403281595",
"3255993615",
"5145721455",
"5254163355",
"5824953435",
"6560751435",
"7176232455",
"7703697855",
"8332635255",
"8542035645"
] | [
"nonn",
"new"
] | 25 | 1 | 1 | [
"A005117",
"A380888",
"A381507"
] | null | Robert Israel, Apr 23 2025 | 2025-04-27T09:50:01 | oeisdata/seq/A381/A381507.seq | f44baa8ea04f64c7af0fa728ea737e62 |
A381508 | Pisano period of Hexanacci numbers (A001592) mod n. | [
"1",
"7",
"728",
"14",
"208",
"728",
"342",
"28",
"2184",
"1456",
"354312",
"728",
"9520",
"2394",
"1456",
"56",
"709928",
"2184",
"5227320",
"1456",
"124488",
"354312",
"279840",
"728",
"1040",
"9520",
"6552",
"2394",
"243880",
"1456",
"71040",
"112",
"4606056",
"4969496",
"35568",
"2184",
"20362908",
"5227320",
"123760",
"1456",
"201840"
] | [
"nonn",
"new"
] | 40 | 1 | 2 | [
"A001175",
"A001592",
"A381508"
] | null | Martin Guerra and Doron Zeilberger, Apr 24 2025 | 2025-04-26T10:25:06 | oeisdata/seq/A381/A381508.seq | 5db27b37dd61024020744384e4d3637a |
A381509 | Numbers whose nonzero digits are in nondecreasing order and any zeros appear at the end. | [
"0",
"1",
"2",
"3",
"4",
"5",
"6",
"7",
"8",
"9",
"10",
"11",
"12",
"13",
"14",
"15",
"16",
"17",
"18",
"19",
"20",
"22",
"23",
"24",
"25",
"26",
"27",
"28",
"29",
"30",
"33",
"34",
"35",
"36",
"37",
"38",
"39",
"40",
"44",
"45",
"46",
"47",
"48",
"49",
"50",
"55",
"56",
"57",
"58",
"59",
"60",
"66",
"67",
"68",
"69",
"70",
"77",
"78",
"79",
"80",
"88",
"89",
"90",
"99",
"100",
"110",
"111",
"112",
"113",
"114",
"115",
"116",
"117"
] | [
"nonn",
"base",
"easy",
"new"
] | 16 | 1 | 3 | [
"A179239",
"A381509"
] | null | Keenin D. Krehbiel, Feb 25 2025 | 2025-04-18T19:08:54 | oeisdata/seq/A381/A381509.seq | 4fe0d9446623dde693c1c04764d372bf |
A381510 | Smaller of two consecutive primes p and q, both ending with 7, such that q - p = 10n, or -1 if no such primes exist. | [
"337",
"887",
"4297",
"33247",
"31907",
"124367",
"218287",
"1122287",
"1964987",
"1313467",
"1468277",
"7160227",
"5518687",
"16525757",
"13626257",
"71880637",
"27915737",
"17051707",
"394059907",
"566348087",
"252314747",
"472865287",
"1289694257",
"633418787",
"1588640437",
"944192807",
"1391048047",
"7059848287"
] | [
"nonn",
"base"
] | 21 | 1 | 1 | [
"A101232",
"A140791",
"A380785",
"A381372",
"A381510"
] | null | Jean-Marc Rebert, Feb 25 2025 | 2025-03-10T12:03:10 | oeisdata/seq/A381/A381510.seq | f3d934b090f2250cab061561194da5ca |
A381511 | Smaller of two consecutive primes p and q, both ending with 9, such that q - p = 10*n, or -1 if no such primes exist. | [
"139",
"3089",
"5749",
"20809",
"60539",
"110359",
"173359",
"618719",
"1294849",
"838249",
"6877109",
"1895359",
"11188759",
"7621259",
"35560009",
"33803689",
"124956059",
"92801029",
"142414669",
"378043979",
"229316459",
"390932389",
"1095750599",
"995151679",
"2174082649",
"2603726969",
"3402493709",
"1997191249"
] | [
"nonn",
"base"
] | 20 | 1 | 1 | [
"A101232",
"A140791",
"A380785",
"A381372",
"A381510",
"A381511"
] | null | Jean-Marc Rebert, Feb 25 2025 | 2025-03-09T12:24:06 | oeisdata/seq/A381/A381511.seq | 8f5f5a402b57869034161ff467c3d675 |
A381514 | a(n) is the hafnian of a symmetric Toeplitz matrix of order 2*n whose off-diagonal element (i,j) equals the |i-j|-th prime. | [
"1",
"2",
"23",
"899",
"85072",
"15120411",
"4439935299",
"1989537541918",
"1264044973158281",
"1090056235155152713",
"1227540523199054294506"
] | [
"nonn",
"hard",
"more"
] | 10 | 0 | 2 | [
"A071078",
"A071079",
"A085807",
"A306457",
"A318173",
"A356483",
"A374067",
"A374068",
"A381514"
] | null | Stefano Spezia, Feb 25 2025 | 2025-02-26T18:12:02 | oeisdata/seq/A381/A381514.seq | fd071baf1629c2b8b465804764f686f5 |
A381515 | a(n) = Sum_{j=1..n} Stirling2(n-1,j-1) * a(n-j) for n>=1, starting with a(0) = 1. | [
"1",
"1",
"1",
"2",
"5",
"16",
"71",
"432",
"3446",
"35805",
"493247",
"9055817",
"219034736",
"6924788187",
"287364757172",
"15747872749912",
"1138063678023858",
"107917571120653077",
"13417659577126888599",
"2194989270698166806727",
"473329783091262653789042",
"134287984058139116699933228"
] | [
"nonn"
] | 12 | 0 | 4 | [
"A000110",
"A008277",
"A048993",
"A308444",
"A381515"
] | null | Alois P. Heinz, Feb 25 2025 | 2025-02-26T09:50:02 | oeisdata/seq/A381/A381515.seq | 5c7b7499a532ae478d14f5dd6deb2888 |
A381516 | a(n) = 1 + number of divisors of n within the sequence up to a(n-1). | [
"1",
"2",
"3",
"3",
"3",
"2",
"7",
"3",
"4",
"6",
"4",
"2",
"12",
"2",
"7",
"6",
"8",
"2",
"13",
"2",
"10",
"8",
"8",
"2",
"21",
"2",
"11",
"6",
"14",
"2",
"19",
"2",
"17",
"7",
"13",
"5",
"22",
"2",
"14",
"8",
"21",
"2",
"28",
"2",
"19",
"7",
"15",
"2",
"30",
"6",
"18",
"7",
"20",
"2",
"26",
"4",
"32",
"8",
"17",
"2",
"35",
"2",
"19",
"13",
"28",
"6",
"30",
"2",
"25",
"6",
"30",
"2",
"41",
"2",
"22",
"9",
"28",
"8",
"36",
"2",
"35"
] | [
"nonn"
] | 18 | 0 | 2 | [
"A027750",
"A056148",
"A381516"
] | null | Austin Blake, Feb 25 2025 | 2025-03-29T04:27:35 | oeisdata/seq/A381/A381516.seq | 57891208bbb216a9f2a75a76ef27939c |
A381517 | Perimeter of the Sierpiński carpet at iteration n. | [
"4",
"16",
"80",
"496",
"3536",
"26992",
"212048",
"1684720",
"13442768",
"107437168",
"859182416",
"6872514544",
"54977282000",
"439809752944",
"3518452514384",
"28147543587568",
"225180119118032",
"1801440264196720",
"14411520047331152",
"115292154179921392",
"922337214843187664",
"7378697662956950896",
"59029581136289955920",
"472236648588222693616"
] | [
"nonn",
"easy"
] | 80 | 0 | 1 | [
"A001018",
"A113210",
"A271939",
"A293143",
"A365606",
"A381517"
] | null | Jakub Buczak, Feb 26 2025 | 2025-03-02T08:02:32 | oeisdata/seq/A381/A381517.seq | 45fe0a7fa43eb5ef3747ff688ca58267 |
A381518 | Expansion of e.g.f. ( (1/x) * Series_Reversion( x/(1 + sin(x))^2 ) )^(1/2). | [
"1",
"1",
"4",
"29",
"304",
"4141",
"68832",
"1337881",
"29432576",
"712263961",
"18403873280",
"487814777141",
"12296236382208",
"230142147098501",
"-2906327530115072",
"-800177574047914831",
"-75835523291585773568",
"-6054072134316123116495",
"-459749417224473755910144",
"-34556942957229166465685555"
] | [
"sign"
] | 8 | 0 | 3 | [
"A136630",
"A198865",
"A381518",
"A381519"
] | null | Seiichi Manyama, Feb 26 2025 | 2025-02-26T06:26:45 | oeisdata/seq/A381/A381518.seq | db14d2aaf0d17a979dd2ef6639c1bb1d |
A381519 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + sin(x))^2 ). | [
"1",
"2",
"10",
"82",
"936",
"13642",
"240656",
"4952218",
"115608704",
"2992207250",
"84070140672",
"2507383885730",
"77117178496000",
"2329071118971482",
"61202811821836288",
"690380688651775978",
"-88097620429234470912",
"-11900508444760552311518",
"-1112180862634722333884416"
] | [
"sign"
] | 11 | 0 | 2 | [
"A136630",
"A377553",
"A381389",
"A381442",
"A381449",
"A381518",
"A381519",
"A381521"
] | null | Seiichi Manyama, Feb 26 2025 | 2025-02-26T06:26:17 | oeisdata/seq/A381/A381519.seq | 657c633348de3b9688ae03483d83a22b |
A381520 | Expansion of e.g.f. ( (1/x) * Series_Reversion( x/(1 + x * cos(x))^2 ) )^(1/2). | [
"1",
"1",
"4",
"27",
"240",
"2345",
"17280",
"-226597",
"-21007616",
"-1007159823",
"-42976972800",
"-1775328986981",
"-72123329507328",
"-2843431148886887",
"-103621659777126400",
"-2971936506262036965",
"-6719764584265482240",
"9528526268302653725537",
"1192610999728818101551104"
] | [
"sign"
] | 12 | 0 | 3 | [
"A185951",
"A381378",
"A381447",
"A381479",
"A381520"
] | null | Seiichi Manyama, Feb 26 2025 | 2025-02-26T06:26:26 | oeisdata/seq/A381/A381520.seq | 1b3717d5d1c01ed05d36b65d6ffbe3e4 |
A381521 | Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x * cos(x))^2 ). | [
"1",
"2",
"10",
"78",
"792",
"9250",
"106080",
"636286",
"-30646784",
"-2237508990",
"-112000654080",
"-5124930562642",
"-227068649702400",
"-9819508698442846",
"-406371251899045888",
"-15094508095346343330",
"-394372545425757634560",
"7096803535075158290434",
"2430273114806112504446976"
] | [
"sign"
] | 11 | 0 | 2 | [
"A185951",
"A377553",
"A381442",
"A381449",
"A381480",
"A381519",
"A381520",
"A381521"
] | null | Seiichi Manyama, Feb 26 2025 | 2025-02-26T06:26:36 | oeisdata/seq/A381/A381521.seq | 9f85b46f3a1cb197886df0b237db990b |
A381522 | a(n) = k after every k^2 occurrences of 1, with multiple values following a 1 listed in order. | [
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"1",
"3",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"4",
"1",
"1",
"3",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"1",
"5",
"1",
"1",
"3",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"4",
"1",
"1",
"1",
"1",
"2",
"3",
"6",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"1",
"3",
"1",
"1",
"1",
"2",
"4",
"1",
"7",
"1",
"5",
"1",
"1",
"2",
"1",
"1",
"3",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"3",
"1",
"2",
"4",
"8",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"2",
"3",
"6"
] | [
"nonn",
"changed"
] | 36 | 1 | 5 | [
"A000188",
"A084580",
"A381456",
"A381522",
"A381900",
"A382093"
] | null | Jwalin Bhatt, Feb 26 2025 | 2025-04-15T21:42:09 | oeisdata/seq/A381/A381522.seq | 162fae851c7a624094b4b7b9dad75b76 |
A381523 | Number of labeled histories for rooted 4-furcating trees with 3n+1 leaves if simultaneous 4-furcations are allowed. | [
"1",
"1",
"35",
"8925",
"8033025",
"19010866875",
"97622651251125",
"958647115051250625",
"16437666902498106890625",
"459581350409578975249546875",
"19861812620603175030206132109375",
"1271123241419341933758758697996796875",
"116303414318027015186301064741488195703125",
"14773177703549629967524262172307456486365234375"
] | [
"nonn"
] | 7 | 0 | 3 | [
"A317059",
"A381486",
"A381523"
] | null | Noah A Rosenberg, Feb 26 2025 | 2025-02-26T09:51:17 | oeisdata/seq/A381/A381523.seq | 16e40d612ab15c5482040b3ab9301287 |
A381524 | Smallest exponent of x of maximal coefficient (ignoring signs) in Hermite polynomial of order n. | [
"0",
"1",
"2",
"1",
"2",
"3",
"2",
"3",
"2",
"3",
"4",
"3",
"4",
"3",
"4",
"5",
"4",
"5",
"4",
"5",
"6",
"5",
"6",
"5",
"6",
"5",
"6",
"7",
"6",
"7",
"6",
"7",
"6",
"7",
"6",
"7",
"8",
"7",
"8",
"7",
"8",
"7",
"8",
"7",
"8",
"9",
"8",
"9",
"8",
"9",
"8",
"9",
"8",
"9",
"10",
"9",
"10",
"9",
"10",
"9",
"10",
"9",
"10",
"9",
"10",
"11",
"10",
"11",
"10",
"11",
"10",
"11",
"10",
"11",
"10",
"11",
"10",
"11",
"12"
] | [
"nonn"
] | 18 | 0 | 3 | [
"A277281",
"A381524",
"A381737"
] | null | Mike Sheppard, Feb 26 2025 | 2025-03-18T07:22:26 | oeisdata/seq/A381/A381524.seq | dab65b9f18f5ec15274095b58aa59c3a |
A381525 | Squarefree semiprimes k = p*q, primes p < q, with q distinct power residues r (mod k) congruent to p^m, m >= 0, and p distinct power residues r (mod k) congruent to q^m, m >= 0. | [
"6",
"10",
"15",
"22",
"26",
"35",
"38",
"51",
"58",
"74",
"85",
"87",
"106",
"115",
"118",
"119",
"122",
"134",
"143",
"159",
"166",
"185",
"187",
"202",
"214",
"215",
"235",
"247",
"262",
"265",
"267",
"278",
"298",
"303",
"319",
"326",
"339",
"346",
"358",
"362",
"365",
"391",
"394",
"411",
"415",
"422",
"427",
"447",
"451",
"454",
"481",
"485",
"515",
"519",
"527"
] | [
"nonn",
"easy"
] | 33 | 1 | 1 | [
"A006881",
"A007947",
"A381525",
"A381804"
] | null | Michael De Vlieger, Mar 24 2025 | 2025-03-29T18:17:28 | oeisdata/seq/A381/A381525.seq | aef00f8cca470080ae7a1c6724472366 |
A381526 | a(n) is the smallest positive integer k such that the decimal expansion of k is a substring of the decimal expansion of n*k, or -1 if no such number exists. | [
"-1",
"1",
"-1",
"5",
"-1",
"5",
"2",
"5",
"-1",
"5",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"-1",
"1",
"9",
"5",
"72",
"5",
"2",
"5",
"6",
"5",
"5",
"1",
"91",
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"42",
"4",
"2",
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"36",
"5",
"-1",
"1",
"94",
"5",
"3",
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"2",
"5",
"8",
"5",
"5",
"1",
"24",
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"5",
"2",
"5",
"21",
"5",
"2",
"1",
"2",
"2",
"2",
"5",
"2",
"5",
"7",
"5",
"5",
"1",
"484",
"5",
"47",
"5",
"2",
"3",
"3",
"3",
"-1"
] | [
"sign",
"base",
"easy",
"look"
] | 16 | 0 | 4 | [
"A239134",
"A337084",
"A381526",
"A381527",
"A381528"
] | null | Dominic McCarty, Feb 26 2025 | 2025-03-03T13:36:48 | oeisdata/seq/A381/A381526.seq | 5e9004502000924837de9d323f0cd8f1 |
A381527 | a(n) is the smallest positive multiple of n such that the decimal expansion of a(n)/n is a substring of the decimal expansion of a(n), or -1 if no such number exists. | [
"-1",
"1",
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"35",
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] | [
"sign",
"easy"
] | 10 | 0 | 4 | [
"A381526",
"A381527"
] | null | Dominic McCarty, Feb 26 2025 | 2025-03-03T13:37:09 | oeisdata/seq/A381/A381527.seq | 509c34cf7eaf3d4be8c94452474e584d |
A381528 | Indices of records in A381526. | [
"0",
"1",
"3",
"22",
"24",
"32",
"42",
"72",
"84",
"384",
"724",
"2584",
"200000002",
"200000004",
"2000000002"
] | [
"nonn"
] | 6 | 1 | 3 | [
"A381526",
"A381528"
] | null | Dominic McCarty, Feb 26 2025 | 2025-03-03T13:37:19 | oeisdata/seq/A381/A381528.seq | 7bcd06fa6d67b6e2c95e0616c38cc11d |
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