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A381115 | Composite terms in A381019 in order of appearance. | [
"4",
"9",
"8",
"6",
"25",
"12",
"10",
"49",
"15",
"16",
"14",
"27",
"20",
"21",
"22",
"18",
"35",
"24",
"169",
"28",
"33",
"26",
"85",
"32",
"57",
"77",
"30",
"34",
"39",
"55",
"38",
"51",
"40",
"91",
"36",
"121",
"42",
"65",
"44",
"45",
"529",
"48",
"119",
"46",
"95",
"81",
"143",
"50",
"63",
"52",
"54",
"115",
"56",
"841",
"187",
"69",
"62",
"125",
"87",
"64",
"133",
"75",
"58",
"221"
] | [
"nonn"
] | 16 | 1 | 1 | [
"A381019",
"A381115",
"A381116",
"A381117"
] | null | N. J. A. Sloane, Feb 14 2025 | 2025-02-15T14:11:57 | oeisdata/seq/A381/A381115.seq | 28548a262b5ec6cf63b04464e9d81f40 |
A381116 | Indices of composite terms in A381019. | [
"7",
"13",
"16",
"23",
"30",
"36",
"47",
"55",
"63",
"64",
"79",
"91",
"100",
"113",
"123",
"142",
"149",
"167",
"178",
"196",
"201",
"223",
"235",
"256",
"259",
"279",
"290",
"325",
"330",
"346",
"364",
"382",
"405",
"422",
"442",
"468",
"485",
"488",
"530",
"534",
"541",
"583",
"605",
"630",
"631",
"665",
"674",
"682",
"729",
"735",
"790",
"798",
"847",
"854",
"862"
] | [
"nonn"
] | 15 | 1 | 1 | [
"A381019",
"A381115",
"A381116",
"A381117"
] | null | N. J. A. Sloane, Feb 14 2025 | 2025-02-15T13:58:39 | oeisdata/seq/A381/A381116.seq | bd5c2dfe107b03f86b5eae0f954278ed |
A381117 | Lengths of runs of consecutive primes in A381019. | [
"5",
"5",
"2",
"6",
"6",
"5",
"10",
"7",
"7",
"14",
"11",
"8",
"12",
"9",
"18",
"6",
"17",
"10",
"17",
"4",
"21",
"11",
"20",
"2",
"19",
"10",
"34",
"4",
"15",
"17",
"17",
"22",
"16",
"19",
"25",
"16",
"2",
"41",
"3",
"6",
"41",
"21",
"24",
"33",
"8",
"7",
"46",
"5",
"54",
"7",
"48",
"6",
"7",
"5",
"41",
"13",
"31",
"18",
"5",
"50",
"1",
"49",
"10",
"26",
"41",
"24",
"45",
"53",
"20",
"21",
"44",
"3"
] | [
"nonn"
] | 10 | 1 | 1 | [
"A381019",
"A381115",
"A381116",
"A381117"
] | null | N. J. A. Sloane, Feb 14 2025 | 2025-02-14T10:19:53 | oeisdata/seq/A381/A381117.seq | b4c46a2eddf9d7b8ca8d2bf0388fabbe |
A381118 | Index of 2^n in A381019. | [
"1",
"2",
"7",
"16",
"64",
"256",
"975",
"3856",
"16647",
"65039",
"260112",
"1044504",
"4177980",
"16777224"
] | [
"nonn",
"more"
] | 14 | 0 | 2 | [
"A381019",
"A381115",
"A381116",
"A381118"
] | null | N. J. A. Sloane, Feb 14 2025 | 2025-02-16T05:40:43 | oeisdata/seq/A381/A381118.seq | 9300a943c45a64672e6fa7ed6fe3d1a7 |
A381119 | Index of n in A381019. | [
"1",
"2",
"3",
"7",
"4",
"23",
"5",
"16",
"13",
"47",
"6",
"36",
"8",
"79",
"63",
"64",
"9",
"142",
"10",
"100",
"113",
"123",
"11",
"167",
"30",
"223",
"91",
"196",
"12",
"290",
"14",
"256",
"201",
"325",
"149",
"442",
"15",
"364",
"330",
"405",
"17",
"485",
"18",
"530",
"534",
"630",
"19",
"583",
"55",
"682",
"382",
"735",
"20",
"790",
"346",
"847",
"259",
"1034",
"21",
"1095"
] | [
"nonn"
] | 24 | 1 | 2 | [
"A381019",
"A381115",
"A381116",
"A381118",
"A381119"
] | null | N. J. A. Sloane, Feb 14 2025 | 2025-02-24T02:07:02 | oeisdata/seq/A381/A381119.seq | dfff77365a92293659bab5540007b92e |
A381120 | Numbers k such that both A381019(k) and A381019(k+1) are composite. | [
"63",
"630",
"2423",
"5653",
"9104",
"26308",
"36108",
"41622",
"64526",
"85121",
"108917",
"143913",
"148305",
"176405",
"316974",
"399168",
"399907",
"406487",
"536926",
"621016",
"830793",
"937038",
"937109",
"970243",
"1088629",
"1480545",
"1895503",
"3961587",
"4651102",
"5171081",
"5487450",
"6219705",
"7327856",
"8118740"
] | [
"nonn"
] | 21 | 1 | 1 | [
"A379810",
"A381019",
"A381120"
] | null | N. J. A. Sloane, Feb 15 2025 | 2025-02-16T21:54:41 | oeisdata/seq/A381/A381120.seq | 51abc73bfd68ee6609133ba2fad12aba |
A381121 | Number of partially ordered sets ("posets") covering n unlabeled elements. | [
"1",
"0",
"1",
"3",
"11",
"47",
"255",
"1727",
"14954",
"166232",
"2384053",
"44182143",
"1058142319",
"32718935706",
"1304369332319",
"66936884741385",
"4414855587293931"
] | [
"nonn",
"hard",
"more"
] | 10 | 0 | 4 | [
"A000112",
"A381121"
] | null | Peter Dolland, Feb 14 2025 | 2025-02-16T10:26:02 | oeisdata/seq/A381/A381121.seq | 391cc049ec484a8b9a963a9d42256d6f |
A381122 | Numbers k such that k^(k+1) == k (mod k+2). | [
"0",
"1",
"4",
"8",
"12",
"20",
"24",
"28",
"32",
"36",
"44",
"56",
"60",
"72",
"80",
"84",
"92",
"104",
"116",
"120",
"132",
"140",
"144",
"156",
"164",
"168",
"176",
"180",
"192",
"200",
"204",
"212",
"216",
"224",
"252",
"260",
"272",
"276",
"296",
"300",
"312",
"324",
"332",
"344",
"356",
"360",
"380",
"384",
"392",
"396",
"420",
"444",
"452",
"456",
"464",
"476",
"480",
"500",
"512",
"524",
"536",
"540",
"552",
"560"
] | [
"nonn"
] | 13 | 1 | 3 | [
"A064935",
"A115976",
"A381122"
] | null | Robert Israel, Feb 14 2025 | 2025-02-15T12:28:19 | oeisdata/seq/A381/A381122.seq | 9c9c4b42c24aa800e97f6d8126af8a88 |
A381123 | Number of unlabeled endofunctions on n points whose self-referencing elements are mapped from another element. | [
"1",
"0",
"2",
"4",
"12",
"28",
"83",
"213",
"608",
"1664",
"4703",
"13173",
"37412",
"105995",
"302301",
"862794",
"2470631",
"7084425",
"20357121",
"58573788",
"168789684",
"486964114",
"1406549550",
"4066751083",
"11769363663",
"34090076148",
"98820914068",
"286672673725",
"832183340955",
"2417270306657",
"7025657374736",
"20430883575932",
"59444386613999",
"173039084438093"
] | [
"nonn"
] | 18 | 0 | 3 | [
"A001372",
"A381123"
] | null | Peter Dolland, Feb 14 2025 | 2025-02-21T12:24:56 | oeisdata/seq/A381/A381123.seq | e2d4bfd5d9b537d61e4d7226aa89b08a |
A381124 | Numerators of convergents to the supergolden ratio. | [
"1",
"3",
"19",
"22",
"85",
"447",
"1873",
"41653",
"43526",
"85179",
"384242",
"469421",
"1323084",
"111608477",
"112931561",
"450403160",
"563334721",
"3830411486",
"4393746207",
"17011650107",
"21405396314",
"209660216933",
"231065613247",
"440725830180",
"671791443427",
"1112517273607",
"21809619641960",
"66541376199487"
] | [
"nonn",
"frac",
"easy"
] | 12 | 0 | 2 | [
"A092526",
"A369346",
"A381124",
"A381125"
] | null | Eric W. Weisstein, Feb 14 2025 | 2025-02-14T23:11:34 | oeisdata/seq/A381/A381124.seq | 9296bc0ec66478428dd9cb493035e0a0 |
A381125 | Denominators of the convergents to the supergolden ratio. | [
"1",
"2",
"13",
"15",
"58",
"305",
"1278",
"28421",
"29699",
"58120",
"262179",
"320299",
"902777",
"76153567",
"77056344",
"307322599",
"384378943",
"2613596257",
"2997975200",
"11607521857",
"14605497057",
"143056995370",
"157662492427",
"300719487797",
"458381980224",
"759101468021",
"14881309872623"
] | [
"nonn",
"frac",
"easy"
] | 11 | 0 | 2 | [
"A092526",
"A369346",
"A381124",
"A381125"
] | null | Eric W. Weisstein, Feb 14 2025 | 2025-02-14T23:11:13 | oeisdata/seq/A381/A381125.seq | 10484718889320399c996f2f0ae7ec93 |
A381126 | Primes that are the concatenation of prime(p) and p where p is a prime. | [
"53",
"6719",
"15737",
"587107",
"1297211",
"1823281",
"1913293",
"3067439",
"3593503",
"3943547",
"4397599",
"5503727",
"5651743",
"6353827",
"6361829",
"6823877",
"7109911",
"7283929",
"7523953",
"85131061",
"85271063",
"87611093",
"88071097",
"104331277",
"125031493",
"128411531",
"130031549",
"133311583",
"141071663"
] | [
"nonn",
"base"
] | 39 | 1 | 1 | [
"A006450",
"A084667",
"A084669",
"A229814",
"A381126"
] | null | Maja Gwozdz, Feb 14 2025 | 2025-02-21T15:24:38 | oeisdata/seq/A381/A381126.seq | 4702af361801b51d5d55acfeefd6687c |
A381127 | Triangle T(n,k) read by rows, where row n is a permutation of the numbers 1 through n, such that if a deck of n cards is prepared in this order, and Down-SpellUnder dealing is used, then the resulting cards will be dealt in increasing order. | [
"1",
"1",
"2",
"1",
"3",
"2",
"1",
"2",
"4",
"3",
"1",
"3",
"5",
"4",
"2",
"1",
"6",
"4",
"3",
"2",
"5",
"1",
"5",
"3",
"6",
"2",
"4",
"7",
"1",
"3",
"4",
"5",
"2",
"7",
"6",
"8",
"1",
"6",
"7",
"9",
"2",
"8",
"5",
"4",
"3",
"1",
"7",
"6",
"5",
"2",
"10",
"4",
"9",
"3",
"8",
"1",
"5",
"10",
"11",
"2",
"4",
"7",
"9",
"3",
"6",
"8",
"1",
"7",
"8",
"4",
"2",
"12",
"6",
"9",
"3",
"11",
"5",
"10",
"1",
"11",
"4",
"6",
"2",
"12",
"13",
"8",
"3",
"5",
"7",
"9",
"10",
"1",
"4",
"9",
"8",
"2",
"12",
"7",
"5",
"3",
"13",
"14",
"11",
"10",
"6"
] | [
"nonn",
"word",
"tabl"
] | 9 | 1 | 3 | [
"A005589",
"A006257",
"A225381",
"A321298",
"A378635",
"A380201",
"A380202",
"A380204",
"A380246",
"A380247",
"A380248",
"A381114",
"A381127",
"A381128",
"A381129"
] | null | Tanya Khovanova, Nathan Sheffield, and the MIT PRIMES STEP junior group, Feb 14 2025 | 2025-03-02T22:55:22 | oeisdata/seq/A381/A381127.seq | 19449aa69e94d5d632b4d0bd9fc36388 |
A381128 | The number of card moves required to deal n cards using Down-SpellUnder dealing. | [
"1",
"5",
"9",
"15",
"20",
"25",
"29",
"35",
"41",
"46",
"50",
"57",
"64",
"73",
"82",
"90",
"98",
"108",
"117",
"126",
"133",
"143",
"153",
"165",
"176",
"187",
"197",
"209",
"221",
"232",
"239",
"249",
"259",
"271",
"282",
"293",
"303",
"315",
"327",
"338",
"344",
"353",
"362",
"373",
"383",
"393",
"402",
"413",
"424",
"434",
"440",
"449",
"458",
"469",
"479",
"489",
"498",
"509",
"520",
"530",
"536",
"545",
"554",
"565",
"575",
"585",
"594",
"605"
] | [
"nonn",
"word"
] | 9 | 1 | 2 | [
"A005589",
"A006257",
"A225381",
"A321298",
"A378635",
"A380201",
"A380202",
"A380204",
"A380246",
"A380247",
"A380248",
"A381114",
"A381127",
"A381128",
"A381129"
] | null | Tanya Khovanova, Nathan Sheffield, and the MIT PRIMES STEP junior group, Feb 14 2025 | 2025-03-14T21:13:25 | oeisdata/seq/A381/A381128.seq | fd11eea9a5eb5a06584eead306d6985f |
A381129 | A version of the Josephus problem: a(n) is the surviving integer under the spelling version of the elimination process, called Down-SpellUnder. | [
"1",
"2",
"2",
"3",
"3",
"2",
"7",
"8",
"4",
"6",
"4",
"6",
"7",
"11",
"10",
"3",
"14",
"4",
"17",
"11",
"3",
"16",
"7",
"16",
"7",
"22",
"2",
"8",
"24",
"27",
"7",
"21",
"13",
"28",
"30",
"8",
"3",
"37",
"12",
"7",
"8",
"33",
"7",
"33",
"44",
"11",
"32",
"8",
"6",
"43",
"2",
"18",
"49",
"8",
"32",
"54",
"26",
"43",
"44",
"30",
"40",
"52",
"26",
"44",
"8",
"27",
"60",
"16",
"11",
"61",
"70",
"14",
"58",
"55"
] | [
"nonn",
"word"
] | 8 | 1 | 2 | [
"A005589",
"A006257",
"A225381",
"A321298",
"A378635",
"A380201",
"A380202",
"A380204",
"A380246",
"A380247",
"A380248",
"A381114",
"A381127",
"A381128",
"A381129"
] | null | Tanya Khovanova, Nathan Sheffield, and the MIT PRIMES STEP junior group, Feb 14 2025 | 2025-02-23T11:29:25 | oeisdata/seq/A381/A381129.seq | 34fed23a9b0e63c05a78423018cc5ba7 |
A381130 | a(n) is the smallest prime not yet in the sequence that contains a substring of size 2 from a(n-1); a(1)=11. | [
"11",
"113",
"13",
"131",
"31",
"311",
"211",
"421",
"521",
"523",
"23",
"223",
"227",
"127",
"271",
"71",
"571",
"157",
"151",
"251",
"257",
"457",
"557",
"577",
"277",
"677",
"67",
"167",
"163",
"263",
"269",
"569",
"563",
"463",
"461",
"61",
"613",
"137",
"37",
"337",
"233",
"239",
"139",
"313",
"317",
"17",
"173",
"73",
"373",
"379",
"79",
"179",
"479",
"47"
] | [
"nonn",
"base",
"changed"
] | 9 | 1 | 1 | [
"A107801",
"A262323",
"A381130"
] | null | Enrique Navarrete, Feb 14 2025 | 2025-04-16T05:31:32 | oeisdata/seq/A381/A381130.seq | f8e582fca70d4144499bd77cf90da130 |
A381131 | If n = (p_1^e_1)*(p_2^e_2)*(p_3^e_3)*... and min(p_1^e_1,p_2^e_2,...) = p_k^e_k then a(n) = p_k, a(1) = 1. | [
"1",
"2",
"3",
"2",
"5",
"2",
"7",
"2",
"3",
"2",
"11",
"3",
"13",
"2",
"3",
"2",
"17",
"2",
"19",
"2",
"3",
"2",
"23",
"3",
"5",
"2",
"3",
"2",
"29",
"2",
"31",
"2",
"3",
"2",
"5",
"2",
"37",
"2",
"3",
"5",
"41",
"2",
"43",
"2",
"5",
"2",
"47",
"3",
"7",
"2",
"3",
"2",
"53",
"2",
"5",
"7",
"3",
"2",
"59",
"3",
"61",
"2",
"7",
"2",
"5",
"2",
"67",
"2",
"3",
"2",
"71",
"2",
"73",
"2",
"3",
"2",
"7",
"2",
"79",
"5"
] | [
"nonn"
] | 8 | 1 | 2 | [
"A020639",
"A034684",
"A088387",
"A381131",
"A381132",
"A381133"
] | null | Ilya Gutkovskiy, Feb 14 2025 | 2025-03-04T23:20:20 | oeisdata/seq/A381/A381131.seq | ec8f31dbf83f077dd5a9b3dfff00b46e |
A381132 | If n = (p_1^e_1)*(p_2^e_2)*(p_3^e_3)*... and min(p_1^e_1,p_2^e_2,...) = p_k^e_k then a(n) = pi(p_k), a(1) = 0. | [
"0",
"1",
"2",
"1",
"3",
"1",
"4",
"1",
"2",
"1",
"5",
"2",
"6",
"1",
"2",
"1",
"7",
"1",
"8",
"1",
"2",
"1",
"9",
"2",
"3",
"1",
"2",
"1",
"10",
"1",
"11",
"1",
"2",
"1",
"3",
"1",
"12",
"1",
"2",
"3",
"13",
"1",
"14",
"1",
"3",
"1",
"15",
"2",
"4",
"1",
"2",
"1",
"16",
"1",
"3",
"4",
"2",
"1",
"17",
"2",
"18",
"1",
"4",
"1",
"3",
"1",
"19",
"1",
"2",
"1",
"20",
"1",
"21",
"1",
"2",
"1",
"4",
"1",
"22",
"3"
] | [
"nonn"
] | 7 | 1 | 3 | [
"A000720",
"A034684",
"A055396",
"A108230",
"A381131",
"A381132",
"A381133"
] | null | Ilya Gutkovskiy, Feb 14 2025 | 2025-03-04T23:20:54 | oeisdata/seq/A381/A381132.seq | b1d5de18c9d33c6e5d39bbc1db9bb208 |
A381133 | If n = (p_1^e_1)*(p_2^e_2)*(p_3^e_3)*... and min(p_1^e_1,p_2^e_2,...) = p_k^e_k then a(n) = e_k, a(1) = 0. | [
"0",
"1",
"1",
"2",
"1",
"1",
"1",
"3",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"4",
"1",
"1",
"1",
"2",
"1",
"1",
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"1",
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"1",
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"1",
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"1",
"1",
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"1",
"6",
"1",
"1",
"1",
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"1",
"1",
"1",
"3",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"4",
"1",
"1",
"1",
"1",
"1",
"1",
"3",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"2"
] | [
"nonn"
] | 8 | 1 | 4 | [
"A034684",
"A051904",
"A088388",
"A381131",
"A381132",
"A381133"
] | null | Ilya Gutkovskiy, Feb 14 2025 | 2025-03-04T23:21:10 | oeisdata/seq/A381/A381133.seq | c817fe8f333a99579e513a9e1f41891c |
A381134 | a(n) = 4*(-3)^n + 3*(-2)^n + 3*2^n - (-3)^n*2^(n + 1) + 2*3^n*(2^n - 2). | [
"0",
"24",
"648",
"96",
"29160",
"384",
"1102248",
"1536",
"40153320",
"6144",
"1449771048",
"24576",
"52230021480",
"98304",
"1880625147048",
"393216",
"67705604657640",
"1572864",
"2437429661950248",
"6291456",
"87747718878685800",
"25165824",
"3158920139068980648",
"100663296",
"113721145341409929960"
] | [
"nonn",
"easy"
] | 11 | 1 | 2 | null | null | Eric W. Weisstein, Feb 21 2025 | 2025-02-21T11:49:34 | oeisdata/seq/A381/A381134.seq | a6370f13cbe9b22af66eca3d38ae067f |
A381135 | Numbers of the form d_1 d_2 d_3 ... where the sum of their digits multiplied by their digit positions is equal to their number of digits. | [
"1",
"20",
"110",
"300",
"1010",
"2100",
"4000",
"10010",
"12000",
"20100",
"31000",
"50000",
"100010",
"111000",
"200100",
"220000",
"301000",
"410000",
"600000",
"1000010",
"1020000",
"1101000",
"1300000",
"2000100",
"2110000",
"3001000",
"3200000",
"4010000",
"5100000",
"7000000",
"10000010",
"10110000",
"11001000",
"12100000"
] | [
"nonn",
"base"
] | 23 | 1 | 2 | [
"A055642",
"A156207",
"A381135"
] | null | Leo Crabbe, Feb 14 2025 | 2025-03-04T23:22:06 | oeisdata/seq/A381/A381135.seq | 8634ee383aa394659f2ccf6353d9cf82 |
A381136 | a(n) is the number of divisors d of n such that tau(d^(1 + n) + n) = 2^omega(d^(1 + n) + n), where tau = A000005 and omega = A001221. | [
"1",
"2",
"0",
"1",
"2",
"4",
"0",
"0",
"1",
"3",
"0",
"2",
"2",
"3",
"0",
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"0",
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"2",
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"8",
"0",
"2",
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"5",
"0",
"1",
"2",
"3",
"0",
"2",
"4",
"8",
"0",
"1",
"1",
"3",
"0",
"4",
"4",
"4",
"0"
] | [
"nonn"
] | 22 | 1 | 2 | [
"A000005",
"A001221",
"A049533",
"A381136",
"A381138"
] | null | Juri-Stepan Gerasimov, Feb 15 2025 | 2025-03-09T17:03:36 | oeisdata/seq/A381/A381136.seq | 3d89967993307fc295ad036760e0c7d3 |
A381137 | Lexicographically earliest sequence of distinct positive integers such that no 3 terms are in harmonic progression. | [
"1",
"2",
"3",
"4",
"5",
"7",
"8",
"9",
"10",
"11",
"12",
"13",
"14",
"16",
"17",
"19",
"21",
"22",
"23",
"25",
"26",
"27",
"29",
"30",
"31",
"32",
"33",
"34",
"35",
"36",
"37",
"38",
"39",
"41",
"43",
"44",
"46",
"47",
"48",
"49",
"50",
"51",
"52",
"53",
"55",
"57",
"58",
"59",
"60",
"61",
"62",
"63",
"64",
"65",
"67",
"68",
"69",
"70",
"71",
"73",
"74",
"76",
"79",
"81",
"82",
"83",
"85",
"86"
] | [
"nonn"
] | 24 | 1 | 2 | [
"A000452",
"A003278",
"A005279",
"A174905",
"A381137"
] | null | Neal Gersh Tolunsky, Feb 15 2025 | 2025-03-12T04:14:49 | oeisdata/seq/A381/A381137.seq | 9069933b422e0f4527de3d79960c8b29 |
A381138 | a(n) is the number of divisors d of n such that tau(n^(1 + d) + d) = 2^omega(n^(1 + d) + d), where tau = A000005 and omega = A001221. | [
"1",
"2",
"1",
"2",
"2",
"4",
"0",
"2",
"1",
"4",
"1",
"4",
"2",
"3",
"2",
"2",
"1",
"3",
"1",
"4",
"2",
"2",
"1",
"3",
"2",
"4",
"1",
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"2",
"8",
"1",
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"3",
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"2",
"2",
"2",
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"1",
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"3",
"1",
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"3",
"1",
"4",
"2",
"4",
"1",
"4",
"1",
"7",
"2",
"4",
"2",
"2",
"4",
"8",
"1",
"1",
"1",
"5",
"1",
"3",
"2",
"4",
"2",
"4",
"2",
"8",
"1",
"3",
"1",
"2",
"1",
"7",
"3",
"4",
"2"
] | [
"nonn"
] | 21 | 1 | 2 | [
"A000005",
"A001221",
"A005117",
"A381136",
"A381138"
] | null | Juri-Stepan Gerasimov, Feb 15 2025 | 2025-03-10T11:11:37 | oeisdata/seq/A381/A381138.seq | 716967f4e24e4a96b3db4bd07e32b0a3 |
A381139 | a(1) = 1, a(2) = 2. Let j = a(n-1) and let d = A160995(j) be the smallest non-divisor of j which shares a prime factor with j. Then for n > 2 a(n) is the smallest multiple of d which is not yet in the sequence. | [
"1",
"2",
"4",
"6",
"8",
"12",
"16",
"18",
"20",
"24",
"9",
"30",
"28",
"36",
"32",
"42",
"40",
"48",
"27",
"54",
"44",
"60",
"56",
"66",
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"72",
"10",
"64",
"78",
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"84",
"80",
"90",
"76",
"96",
"45",
"102",
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"108",
"104",
"114",
"92",
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"100",
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"138",
"116",
"144",
"50",
"124",
"150",
"128",
"156",
"136",
"162",
"140",
"168",
"81",
"174"
] | [
"nonn",
"easy"
] | 19 | 1 | 2 | [
"A160995",
"A337687",
"A381139"
] | null | David James Sycamore and Michael De Vlieger, Feb 15 2025 | 2025-04-04T22:34:06 | oeisdata/seq/A381/A381139.seq | 718e0361795151fa8f0229b83daa1466 |
A381140 | Expansion of e.g.f. exp( -LambertW(-x * cosh(x)) ). | [
"1",
"1",
"3",
"19",
"161",
"1781",
"24667",
"409991",
"7959233",
"176920489",
"4432942931",
"123648692795",
"3800647961761",
"127654261471517",
"4651982506605995",
"182824074836850991",
"7708128977570816129",
"347059689259637711441",
"16621016953663100702755",
"843658152872351669816675"
] | [
"nonn"
] | 15 | 0 | 3 | [
"A003727",
"A162649",
"A185951",
"A381140",
"A381143"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-16T08:34:07 | oeisdata/seq/A381/A381140.seq | 1d8782489b7d70d771e24068a72a5d03 |
A381141 | Expansion of e.g.f. exp( -LambertW(-x * cos(x)) ). | [
"1",
"1",
"3",
"13",
"89",
"821",
"9667",
"137817",
"2306705",
"44308009",
"960645251",
"23205700453",
"618086944873",
"17996847978461",
"568729575572355",
"19387150575025201",
"709130794848586657",
"27704208465508996945",
"1151379111946617111043",
"50721472225191792506301",
"2360928161776701549045241"
] | [
"nonn"
] | 13 | 0 | 3 | [
"A009189",
"A185951",
"A381141",
"A381144",
"A381146"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-16T08:34:07 | oeisdata/seq/A381/A381141.seq | e474796d1523df420508b97c893272fc |
A381142 | Expansion of e.g.f. exp( -LambertW(-sin(x)) ). | [
"1",
"1",
"3",
"15",
"113",
"1137",
"14355",
"218239",
"3883585",
"79218721",
"1822842243",
"46717337007",
"1319891043569",
"40759239427857",
"1365932381706963",
"49373610759452575",
"1914856819983977473",
"79316216447375396161",
"3494800326874932467331",
"163218136611270923087439"
] | [
"nonn"
] | 11 | 0 | 3 | [
"A002017",
"A136630",
"A185690",
"A277498",
"A381142",
"A381145",
"A381148"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-16T08:34:07 | oeisdata/seq/A381/A381142.seq | ac8ecddd6d147957ebf63533da49528f |
A381143 | Expansion of e.g.f. (1/x) * Series_Reversion( x * exp(-x * cosh(x)) ). | [
"1",
"1",
"3",
"19",
"185",
"2381",
"38227",
"739271",
"16752465",
"435437209",
"12772234211",
"417396070235",
"15040805940745",
"592531894182437",
"25336144876513395",
"1168670193628654351",
"57845446906144852769",
"3058248577410499021361",
"172007282950136451003331",
"10255035157348348977955619"
] | [
"nonn"
] | 9 | 0 | 3 | [
"A003727",
"A162649",
"A185951",
"A381140",
"A381143"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:12:00 | oeisdata/seq/A381/A381143.seq | e471a9895a35ceeb236f9ce79c4c3aef |
A381144 | Expansion of e.g.f. (1/x) * Series_Reversion( x * exp(-x * cos(x)) ). | [
"1",
"1",
"3",
"13",
"65",
"221",
"-2933",
"-120903",
"-3104127",
"-71637191",
"-1562635789",
"-31373685947",
"-505087300991",
"-1692007785259",
"402032879446395",
"28152810613025521",
"1423083552938781697",
"62552808878706976625",
"2459148829654813484131",
"82692880516086149155581"
] | [
"sign"
] | 10 | 0 | 3 | [
"A009189",
"A185951",
"A381141",
"A381144",
"A381146"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:11:48 | oeisdata/seq/A381/A381144.seq | e2a4b16110280309955881664a611559 |
A381145 | Expansion of e.g.f. (1/x) * Series_Reversion( x * exp(-sin(x)) ). | [
"1",
"1",
"3",
"15",
"105",
"937",
"10059",
"124607",
"1720593",
"25578001",
"391041299",
"5628440015",
"55397475705",
"-847789025159",
"-93469767131685",
"-5040670692970753",
"-236210967512228575",
"-10629917015586704351",
"-475183316832486106589",
"-21394016956935371375601",
"-975459739630268065696887"
] | [
"sign"
] | 10 | 0 | 3 | [
"A002017",
"A136630",
"A185690",
"A334856",
"A381142",
"A381145",
"A381148"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:11:31 | oeisdata/seq/A381/A381145.seq | 3ef4f40e24f72eabad79fe029fca9bf5 |
A381146 | E.g.f. A(x) satisfies A(x) = exp( x * cos(x * A(x)) ). | [
"1",
"1",
"1",
"-2",
"-35",
"-264",
"-1019",
"9864",
"302905",
"4181824",
"23080201",
"-632195200",
"-25239729899",
"-478790195584",
"-2682065360883",
"188875659540736",
"8843706554450033",
"203538869514047488",
"751681101659548177",
"-169782541027003551744",
"-8866196526809624969139"
] | [
"sign"
] | 10 | 0 | 4 | [
"A009189",
"A185951",
"A381141",
"A381144",
"A381146"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:11:52 | oeisdata/seq/A381/A381146.seq | 9f6c2d7006f560161cc38054e4d70d68 |
A381147 | E.g.f. A(x) satisfies A(x) = exp( sinh(x * A(x)) / A(x) ). | [
"1",
"1",
"1",
"2",
"13",
"92",
"621",
"5112",
"56057",
"705168",
"9480665",
"141039648",
"2366242693",
"43609330624",
"864164283269",
"18414385180544",
"422574196387953",
"10374625080684800",
"270563138370828465",
"7472794772378583552",
"218190569313134267517",
"6714970997524417977344"
] | [
"nonn"
] | 11 | 0 | 4 | [
"A003724",
"A136630",
"A162650",
"A219503",
"A381147"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:11:44 | oeisdata/seq/A381/A381147.seq | 7fef309c1bcff89748f610f3835a5a35 |
A381148 | E.g.f. A(x) satisfies A(x) = exp( sin(x * A(x)) / A(x) ). | [
"1",
"1",
"1",
"0",
"-11",
"-88",
"-459",
"-560",
"27945",
"502336",
"5223945",
"18968576",
"-671465123",
"-20909349888",
"-345616002627",
"-2437013715968",
"65881260463697",
"3252353828442112",
"76987773739473809",
"873339053357432832",
"-17521718791602049595",
"-1354633521318944473088"
] | [
"sign"
] | 8 | 0 | 5 | [
"A002017",
"A136630",
"A185690",
"A381142",
"A381145",
"A381148"
] | null | Seiichi Manyama, Feb 15 2025 | 2025-02-15T10:11:26 | oeisdata/seq/A381/A381148.seq | 4770fb5b05a847079b87a86de6390289 |
A381149 | a(1) = 2, a(2) = 3; thereafter, a(n) = a(n-1) + sum of prior prime terms. | [
"2",
"3",
"8",
"13",
"31",
"80",
"129",
"178",
"227",
"503",
"1282",
"2061",
"2840",
"3619",
"4398",
"5177",
"5956",
"6735",
"7514",
"8293",
"17365",
"26437",
"61946",
"97455",
"132964",
"168473",
"203982",
"239491",
"275000",
"310509",
"346018",
"381527",
"798563",
"1215599",
"1632635",
"2049671",
"2466707",
"5350450",
"8234193",
"11117936"
] | [
"nonn"
] | 21 | 1 | 1 | [
"A101135",
"A119746",
"A131093",
"A381149",
"A381150"
] | null | James C. McMahon, Feb 15 2025 | 2025-02-25T14:54:42 | oeisdata/seq/A381/A381149.seq | 408a44939b70718f40f8f9a0ae626308 |
A381150 | a(0) = 1, a(1) = 2, a(2) = 3; thereafter, a(n) = a(n-1) + (sum of prior prime terms or whose negatives are prime) - (sum of prior composite terms or whose negatives are composite). | [
"1",
"2",
"3",
"8",
"5",
"7",
"16",
"9",
"-7",
"-30",
"-23",
"-39",
"-16",
"23",
"85",
"62",
"-23",
"-131",
"-370",
"-239",
"-347",
"-802",
"-455",
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"1496",
"1149",
"-347",
"-2190",
"-1843",
"347",
"2884",
"2537",
"-347",
"-3578",
"-3231",
"347",
"4272",
"3925",
"-347",
"-4966",
"-4619",
"347",
"5660",
"5313",
"-347",
"-6354",
"-6007",
"-11667",
"-5660"
] | [
"sign"
] | 22 | 0 | 2 | [
"A000040",
"A002808",
"A101135",
"A119746",
"A131093",
"A381149",
"A381150"
] | null | James C. McMahon, Feb 15 2025 | 2025-02-25T09:44:12 | oeisdata/seq/A381/A381150.seq | 3e28a44a4155ca73205a303cbc4192a4 |
A381151 | The order of the 13 cards of one suit such that after Down-SpellUnder dealing the cards are in order; a(n) is the n-th card in the deck. | [
"1",
"11",
"4",
"6",
"2",
"12",
"13",
"8",
"3",
"5",
"7",
"9",
"10"
] | [
"nonn",
"fini",
"full",
"word"
] | 16 | 1 | 2 | [
"A005589",
"A006257",
"A225381",
"A321298",
"A378635",
"A380201",
"A380202",
"A380204",
"A380246",
"A380247",
"A380248",
"A381151"
] | null | Tanya Khovanova, Nathan Sheffield, and the MIT PRIMES STEP junior group, Feb 15 2025 | 2025-03-24T01:26:53 | oeisdata/seq/A381/A381151.seq | d6e57dfa746879ed2412b995c3eb7b75 |
A381152 | Decimal expansion of the isoperimetric quotient of a regular pentagon. | [
"8",
"6",
"4",
"8",
"0",
"6",
"2",
"6",
"5",
"9",
"7",
"7",
"2",
"0",
"9",
"9",
"6",
"7",
"2",
"3",
"1",
"1",
"8",
"2",
"0",
"6",
"5",
"8",
"5",
"8",
"6",
"2",
"3",
"3",
"3",
"7",
"0",
"3",
"8",
"2",
"8",
"5",
"5",
"5",
"6",
"9",
"0",
"2",
"2",
"8",
"3",
"9",
"9",
"6",
"2",
"1",
"3",
"2",
"0",
"9",
"5",
"7",
"3",
"9",
"8",
"9",
"3",
"3",
"2",
"7",
"0",
"9",
"3",
"4",
"1",
"1",
"8",
"7",
"1",
"2",
"9",
"6",
"4",
"8",
"0",
"4",
"0",
"2",
"3",
"3"
] | [
"nonn",
"cons",
"easy"
] | 12 | 0 | 1 | [
"A003881",
"A019952",
"A073010",
"A093766",
"A102771",
"A196522",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:09 | oeisdata/seq/A381/A381152.seq | ac16ba7789b2f9817daed5b90bcc8fa1 |
A381153 | Decimal expansion of the isoperimetric quotient of a regular heptagon. | [
"9",
"3",
"1",
"9",
"4",
"0",
"6",
"2",
"3",
"4",
"9",
"9",
"0",
"9",
"5",
"7",
"4",
"5",
"9",
"5",
"2",
"2",
"2",
"6",
"3",
"0",
"0",
"8",
"9",
"4",
"2",
"2",
"7",
"5",
"4",
"5",
"7",
"4",
"5",
"2",
"8",
"5",
"2",
"5",
"1",
"5",
"4",
"7",
"1",
"5",
"3",
"1",
"5",
"6",
"1",
"2",
"7",
"3",
"2",
"0",
"2",
"2",
"6",
"8",
"8",
"6",
"4",
"5",
"2",
"5",
"3",
"9",
"4",
"8",
"0",
"5",
"4",
"7",
"8",
"5",
"6",
"9",
"3",
"7",
"7",
"2",
"8",
"6",
"7",
"1"
] | [
"nonn",
"cons",
"easy"
] | 7 | 0 | 1 | [
"A003881",
"A073010",
"A093766",
"A178817",
"A196522",
"A343058",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:30 | oeisdata/seq/A381/A381153.seq | 7a2b58698dccb5e2e007734cb3f173f3 |
A381154 | Decimal expansion of the isoperimetric quotient of a regular 9-gon. | [
"9",
"5",
"9",
"0",
"5",
"0",
"5",
"4",
"1",
"8",
"7",
"3",
"6",
"0",
"9",
"3",
"5",
"8",
"0",
"7",
"4",
"5",
"4",
"3",
"3",
"0",
"6",
"7",
"0",
"8",
"6",
"4",
"3",
"4",
"1",
"3",
"0",
"2",
"0",
"1",
"8",
"1",
"5",
"8",
"0",
"9",
"7",
"5",
"2",
"8",
"5",
"8",
"7",
"3",
"4",
"3",
"7",
"2",
"0",
"7",
"8",
"9",
"2",
"8",
"0",
"3",
"9",
"1",
"9",
"4",
"5",
"1",
"0",
"3",
"7",
"5",
"6",
"4",
"9",
"7",
"6",
"1",
"4",
"4",
"0",
"5",
"7",
"7",
"1",
"2"
] | [
"nonn",
"cons",
"easy"
] | 7 | 0 | 1 | [
"A003881",
"A019918",
"A073010",
"A093766",
"A196522",
"A256853",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:32 | oeisdata/seq/A381/A381154.seq | 3c35261dfbe97d8946764a626cfd7938 |
A381155 | Decimal expansion of the isoperimetric quotient of a regular 10-gon. | [
"9",
"6",
"6",
"8",
"8",
"2",
"7",
"9",
"9",
"0",
"4",
"6",
"4",
"0",
"2",
"5",
"4",
"0",
"3",
"2",
"8",
"1",
"8",
"3",
"2",
"1",
"9",
"1",
"8",
"2",
"7",
"5",
"2",
"9",
"8",
"8",
"4",
"6",
"9",
"8",
"6",
"8",
"2",
"4",
"1",
"0",
"8",
"4",
"4",
"0",
"4",
"2",
"9",
"1",
"1",
"0",
"9",
"9",
"3",
"6",
"4",
"1",
"5",
"1",
"8",
"4",
"4",
"7",
"6",
"9",
"2",
"9",
"5",
"1",
"0",
"1",
"3",
"1",
"0",
"2",
"1",
"4",
"3",
"7",
"9",
"2",
"2",
"0",
"5",
"5"
] | [
"nonn",
"cons",
"easy"
] | 7 | 0 | 1 | [
"A003881",
"A019916",
"A073010",
"A093766",
"A178816",
"A196522",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:39 | oeisdata/seq/A381/A381155.seq | 779290708c856b945a5e3c20e2fbcc06 |
A381156 | Decimal expansion of the isoperimetric quotient of a regular 11-gon. | [
"9",
"7",
"2",
"6",
"6",
"2",
"0",
"0",
"0",
"9",
"1",
"9",
"9",
"0",
"6",
"8",
"1",
"9",
"5",
"3",
"8",
"2",
"8",
"8",
"9",
"7",
"9",
"3",
"8",
"5",
"2",
"6",
"7",
"6",
"3",
"1",
"7",
"1",
"2",
"9",
"6",
"5",
"4",
"1",
"1",
"1",
"4",
"2",
"3",
"4",
"2",
"8",
"8",
"2",
"7",
"3",
"7",
"9",
"8",
"9",
"0",
"4",
"7",
"0",
"0",
"5",
"8",
"7",
"1",
"2",
"6",
"7",
"8",
"3",
"2",
"5",
"6",
"9",
"3",
"0",
"8",
"0",
"2",
"3",
"1",
"7",
"8",
"7",
"5",
"0"
] | [
"nonn",
"cons",
"easy"
] | 7 | 0 | 1 | [
"A003881",
"A073010",
"A093766",
"A196522",
"A256854",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:48 | oeisdata/seq/A381/A381156.seq | 015e70b4c72eef6c4271c8bef0373d53 |
A381157 | Decimal expansion of the isoperimetric quotient of a regular 12-gon. | [
"9",
"7",
"7",
"0",
"4",
"8",
"6",
"1",
"6",
"6",
"5",
"6",
"8",
"5",
"3",
"3",
"3",
"5",
"7",
"2",
"5",
"6",
"2",
"6",
"7",
"9",
"4",
"9",
"5",
"7",
"1",
"2",
"2",
"7",
"4",
"7",
"1",
"0",
"3",
"8",
"7",
"8",
"1",
"2",
"8",
"5",
"8",
"5",
"7",
"0",
"2",
"7",
"8",
"0",
"7",
"2",
"1",
"6",
"2",
"8",
"6",
"6",
"5",
"8",
"9",
"8",
"3",
"3",
"3",
"5",
"2",
"9",
"6",
"6",
"2",
"6",
"2",
"3",
"3",
"0",
"4",
"0",
"2",
"5",
"7",
"0",
"3",
"7",
"1",
"7"
] | [
"nonn",
"cons",
"easy"
] | 6 | 0 | 1 | [
"A003881",
"A019913",
"A073010",
"A093766",
"A178809",
"A196522",
"A381152",
"A381153",
"A381154",
"A381155",
"A381156",
"A381157"
] | null | Paolo Xausa, Feb 15 2025 | 2025-02-15T16:49:57 | oeisdata/seq/A381/A381157.seq | b355aab39a1db173659844ea3c6af3cf |
A381158 | Prime numbers where digit values decrease while alternating parity. | [
"2",
"3",
"5",
"7",
"41",
"43",
"61",
"83",
"521",
"541",
"743",
"761",
"941",
"983",
"6521",
"8521",
"8543",
"8741",
"8761",
"76541",
"76543",
"94321",
"98321",
"98543"
] | [
"nonn",
"base",
"fini",
"full"
] | 28 | 1 | 1 | [
"A000040",
"A028864",
"A028867",
"A052014",
"A052015",
"A381158",
"A382027"
] | null | James S. DeArmon, Feb 15 2025 | 2025-03-20T10:32:04 | oeisdata/seq/A381/A381158.seq | 8764f5fbfb31261c94d1c7d66b939a17 |
A381159 | Numbers whose prime divisors all end in the same digit. | [
"1",
"2",
"3",
"4",
"5",
"7",
"8",
"9",
"11",
"13",
"16",
"17",
"19",
"23",
"25",
"27",
"29",
"31",
"32",
"37",
"39",
"41",
"43",
"47",
"49",
"53",
"59",
"61",
"64",
"67",
"69",
"71",
"73",
"79",
"81",
"83",
"89",
"97",
"101",
"103",
"107",
"109",
"113",
"117",
"119",
"121",
"125",
"127",
"128",
"129",
"131",
"137",
"139",
"149",
"151",
"157",
"159",
"163",
"167",
"169",
"173",
"179"
] | [
"nonn",
"base"
] | 37 | 1 | 2 | [
"A000079",
"A000351",
"A000961",
"A004615",
"A004618",
"A090652",
"A380758",
"A381159"
] | null | Alexander M. Domashenko, Feb 15 2025 | 2025-02-21T07:19:45 | oeisdata/seq/A381/A381159.seq | c3c257b36913da344e42fc0cfb64f77a |
A381160 | a(n) is the permanent of the n X n matrix whose element (i,j) is equal to A008277(i+3, j) with 1 <= i,j <= n. | [
"1",
"1",
"22",
"3206",
"1902936",
"3504528354",
"16660734321540",
"179059038168086056",
"3938830136216956996632",
"164125096331945477980176920",
"12173562237817299484378342192768",
"1527294306324982018922212102518520032",
"310564445230567070838152555220146533261496",
"98712056006032672983172826864304778359411112064"
] | [
"nonn"
] | 11 | 0 | 3 | [
"A000442",
"A008277",
"A381160",
"A381166"
] | null | Stefano Spezia, Feb 15 2025 | 2025-02-16T05:40:27 | oeisdata/seq/A381/A381160.seq | b3df5b923481e54113e014013ff2cdda |
A381161 | a(n) = (10*n)!/((n!)^3*(2*n)!*(5*n)!). | [
"1",
"15120",
"3491888400",
"1304290155168000",
"601680868708529610000",
"312696069714024464473125120",
"175460887238127057573116837126400",
"103865765423748548466734695459219968000",
"63958974275578307119821712720619705931210000",
"40596987692554701292235753375257230410967703200000"
] | [
"nonn"
] | 9 | 0 | 2 | [
"A000442",
"A010050",
"A100734",
"A195394",
"A381161",
"A381162",
"A381163",
"A381164",
"A381165"
] | null | Stefano Spezia, Feb 15 2025 | 2025-02-16T04:40:29 | oeisdata/seq/A381/A381161.seq | 02abcfa4443690d84991f1150b862821 |
A381162 | a(n) = (8*n)!/((n!)^4*(4*n)!). | [
"1",
"1680",
"32432400",
"999456057600",
"37905932634570000",
"1617318175088527591680",
"74451445170005824874553600",
"3614146643656788883257309696000",
"182458061523203642337177421198794000",
"9493111901274733909567003010522405280000",
"505860213332178847817809654781948251947782400"
] | [
"nonn"
] | 10 | 0 | 2 | [
"A100733",
"A134375",
"A195392",
"A381161",
"A381162",
"A381163",
"A381164",
"A381165"
] | null | Stefano Spezia, Feb 15 2025 | 2025-02-19T13:00:14 | oeisdata/seq/A381/A381162.seq | 29cfc3b5c9550df75f04a27f91fe5959 |
A381163 | a(n) = Sum_{k=0..n} binomial(n,k)*(4*k)!*(2*k)!/(k!)^6. | [
"1",
"49",
"15217",
"7437505",
"4444068913",
"2978797867489",
"2151085262277121",
"1636678166183569873",
"1294384621280668799665",
"1054623536679756097536097",
"879831837105310233485202337",
"748258333337818719124808979313",
"646586399881218539235007860940609",
"566284969531710881501724274920081265"
] | [
"nonn"
] | 16 | 0 | 2 | [
"A007318",
"A010050",
"A100733",
"A307618",
"A381161",
"A381162",
"A381163",
"A381164",
"A381165"
] | null | Stefano Spezia, Feb 15 2025 | 2025-04-01T03:29:06 | oeisdata/seq/A381/A381163.seq | fb8fab125c5b37ad77a166bc0f681687 |
A381164 | a(n) = Sum_{k=0..n} binomial(n,k)*(5*k)!/(k!)^5. | [
"1",
"121",
"113641",
"168508561",
"306213587881",
"624890127114721",
"1374618918516663841",
"3187068298971939367561",
"7682172545187676630759081",
"19079663136489248380982551201",
"48525227073661262262248690661841",
"125818607409307965748858681991235961",
"331488456546076036761442657285875590881"
] | [
"nonn"
] | 17 | 0 | 2 | [
"A007318",
"A008978",
"A100734",
"A381161",
"A381162",
"A381163",
"A381164",
"A381165"
] | null | Stefano Spezia, Feb 15 2025 | 2025-04-01T03:29:11 | oeisdata/seq/A381/A381164.seq | 760da5392f72c5d8e91f4d621e210ec6 |
A381165 | a(n) = Sum_{k=0..n} binomial(2*n,n)*binomial(n, k)*(5*k)!/((k!)^3*(2*k)!). | [
"1",
"122",
"114126",
"169305620",
"307902541870",
"628881704226972",
"1384648756554128604",
"3213280613371692112392",
"7752574653184355259506670",
"19272593072633780827550508620",
"49062146831202726778631520779476",
"127331178560917294198014376933764792",
"335791906923524740189894975371277920796"
] | [
"nonn"
] | 12 | 0 | 2 | [
"A000442",
"A000984",
"A007318",
"A010050",
"A100734",
"A381161",
"A381162",
"A381163",
"A381164",
"A381165"
] | null | Stefano Spezia, Feb 15 2025 | 2025-04-01T05:29:53 | oeisdata/seq/A381/A381165.seq | bd37c67b1cdd8dd94d948005b2bebf51 |
A381166 | a(n) is the permanent of the n X n matrix whose element (i,j) is equal to A008277(i+4, j) with 1 <= i,j <= n. | [
"1",
"1",
"46",
"23216",
"70437736",
"911400637082",
"39931366088759328",
"5015203546888139970264",
"1592320463242701429692077472",
"1158339311156769223634640734447744",
"1783702957209729441902140461938160455424",
"5447268928199100257603373050876725987854119216",
"31237114830378466799129128930824084710690680271414364"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A008277",
"A134375",
"A381160",
"A381166"
] | null | Stefano Spezia, Feb 15 2025 | 2025-02-16T05:40:23 | oeisdata/seq/A381/A381166.seq | 0881174c1939d369ca089e9bd9fb4199 |
A381167 | Each term is the least positive integer not appearing earlier such that gcd(a(m),a(n)) = 1 or |m-n| > max(a(m),a(n)) for all m <> n. | [
"1",
"2",
"3",
"5",
"7",
"11",
"4",
"13",
"17",
"19",
"23",
"29",
"9",
"31",
"37",
"8",
"41",
"43",
"47",
"53",
"59",
"61",
"67",
"71",
"6",
"73",
"79",
"83",
"89",
"25",
"97",
"101",
"103",
"107",
"109",
"113",
"127",
"12",
"131",
"137",
"139",
"149",
"151",
"157",
"163",
"167",
"173",
"179",
"181",
"191",
"193",
"197",
"14",
"199",
"211",
"15",
"223",
"227",
"229",
"233",
"239",
"241",
"251",
"257",
"263",
"269",
"271",
"277"
] | [
"nonn"
] | 16 | 1 | 2 | [
"A381019",
"A381167"
] | null | M. F. Hasler and Ali Sada, Feb 15 2025 | 2025-02-15T23:43:35 | oeisdata/seq/A381/A381167.seq | 934086853b4c99d3cb51cc42a789e56c |
A381168 | Number of minimal dominating sets in the n-Hanoi graph. | [
"3",
"27",
"16940"
] | [
"nonn",
"bref",
"more"
] | 4 | 1 | 1 | null | null | Eric W. Weisstein, Feb 15 2025 | 2025-02-15T20:41:53 | oeisdata/seq/A381/A381168.seq | 6fba0b0b6453c54971ddb5a704fafc05 |
A381169 | List of twin prime averages (A014574) is partitioned by including as many elements as possible in the n-th partition, L_n, such that any gap in L_n is smaller than the gap between L_n and L_(n-1) but not bigger than the first gap in L_n. a(n) is the number of elements in L_n. | [
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"2",
"2",
"3",
"2",
"2",
"1",
"1",
"2",
"1",
"6",
"3",
"2",
"2",
"2",
"1",
"1",
"5",
"2",
"2",
"2",
"3",
"1",
"2",
"2",
"2",
"2",
"3",
"2",
"2",
"1",
"2",
"4",
"2",
"2",
"2",
"2",
"5",
"2",
"2",
"1",
"1",
"1",
"3",
"2",
"2",
"1",
"3",
"3",
"2",
"1",
"4",
"2",
"3",
"2",
"2",
"1",
"2",
"2",
"3",
"3",
"1",
"3",
"2",
"1",
"2",
"1",
"1",
"2",
"3",
"3",
"1",
"1",
"2",
"2",
"3",
"2",
"2",
"1",
"5",
"2"
] | [
"nonn"
] | 11 | 1 | 7 | [
"A001097",
"A014574",
"A348168",
"A381169"
] | null | Ya-Ping Lu, Feb 15 2025 | 2025-03-02T23:54:20 | oeisdata/seq/A381/A381169.seq | 31856c6ede97febcab6718b687ce7567 |
A381170 | Euler transform of n^2 * A065959(n). | [
"1",
"1",
"37",
"289",
"2107",
"14329",
"105187",
"693579",
"4512054",
"28468770",
"176428599",
"1065826203",
"6323626404",
"36816785552",
"210944620532",
"1189766311028",
"6615412814561",
"36287015790029",
"196547683500294",
"1051919158699442",
"5566679104757415",
"29144209704259923",
"151039019038054896"
] | [
"nonn"
] | 29 | 0 | 3 | [
"A065959",
"A156733",
"A381170",
"A381709"
] | null | Seiichi Manyama, Mar 04 2025 | 2025-04-01T03:28:25 | oeisdata/seq/A381/A381170.seq | 6624a5bf0c8bc629d0646529c1d859f7 |
A381171 | Expansion of e.g.f. (1/x) * Series_Reversion( x / (1 + x*cosh(x)) ). | [
"1",
"1",
"2",
"9",
"72",
"725",
"8640",
"124117",
"2117248",
"41477193",
"913305600",
"22371549761",
"604476094464",
"17858943664861",
"572524035586048",
"19793963392789965",
"734249332747960320",
"29090332675789113617",
"1225991945551031304192",
"54765451909152748484857",
"2584803582762012599910400"
] | [
"nonn"
] | 13 | 0 | 3 | [
"A162653",
"A162654",
"A185951",
"A215364",
"A381171",
"A381172",
"A381173",
"A381181"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T09:41:01 | oeisdata/seq/A381/A381171.seq | 091dd606a3f795ec155c0883ddc8b922 |
A381172 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x)^2 * cosh(x * A(x)) ). | [
"1",
"1",
"6",
"75",
"1416",
"36065",
"1160400",
"45182347",
"2066343552",
"108594342369",
"6449557524480",
"427226389872491",
"31230489190382592",
"2497416890105693569",
"216875134620623990784",
"20324880119519860657515",
"2044641793664946681446400",
"219762483007148574205773377",
"25134006030221243013604835328"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A162654",
"A185951",
"A215364",
"A364984",
"A381171",
"A381172",
"A381175"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T09:41:04 | oeisdata/seq/A381/A381172.seq | 943db2456698894eedc036e4ea550e8e |
A381173 | Expansion of e.g.f. (1/x) * Series_Reversion( x / (1 + x*cos(x)) ). | [
"1",
"1",
"2",
"3",
"-24",
"-475",
"-5760",
"-52297",
"-155008",
"8781705",
"313344000",
"6966991339",
"102864807936",
"18664712365",
"-71473582229504",
"-3387816787568865",
"-103478592573112320",
"-1899945146589964783",
"18941335827815596032",
"3808766537454425974739",
"215681241589289359769600"
] | [
"sign"
] | 12 | 0 | 3 | [
"A162653",
"A185951",
"A381171",
"A381173",
"A381174",
"A381175",
"A381176",
"A381181"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T09:41:08 | oeisdata/seq/A381/A381173.seq | 269a8a2abd4bce9e64aaeb64dd26aff9 |
A381174 | Expansion of e.g.f. (1/x) * Series_Reversion( x * (1 - x*cos(x)) ). | [
"1",
"1",
"4",
"27",
"264",
"3365",
"52800",
"980903",
"20984320",
"506078505",
"13525493760",
"394758794419",
"12414039171072",
"414990179398093",
"14523823020621824",
"521523225315049215",
"18594912994237808640",
"613842569215361446097",
"14735570097970682265600",
"-228398321523777856462261"
] | [
"sign"
] | 11 | 0 | 3 | [
"A185951",
"A381173",
"A381174",
"A381175",
"A381176"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T09:41:12 | oeisdata/seq/A381/A381174.seq | 7484752264d3e1eec346be4e7012d8cc |
A381175 | E.g.f. A(x) satisfies A(x) = 1/( 1 - x * A(x)^2 * cos(x * A(x)) ). | [
"1",
"1",
"6",
"69",
"1224",
"29465",
"898320",
"33187133",
"1441200768",
"71956238769",
"4061414246400",
"255737764687669",
"17773804761259008",
"1351494159065894857",
"111608708333568036864",
"9947544079380663728685",
"951770403836914402099200",
"97301151510219112917218657",
"10585077723403580668983902208"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A185951",
"A364984",
"A381172",
"A381173",
"A381174",
"A381175",
"A381176"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:05:51 | oeisdata/seq/A381/A381175.seq | d54fda792f6fea9f2bcc0c13e31ba6ac |
A381176 | E.g.f. A(x) satisfies A(x) = 1 + x*cos(x*A(x)). | [
"1",
"1",
"0",
"-3",
"-24",
"-55",
"480",
"8813",
"61824",
"-264591",
"-13662720",
"-185252771",
"-117427200",
"52162650553",
"1214778679296",
"7998339208845",
"-370278535495680",
"-14623177924271263",
"-202753399336206336",
"3863010744775239101",
"286065782789626920960",
"6603193175290504771881"
] | [
"sign"
] | 10 | 0 | 4 | [
"A185951",
"A381173",
"A381174",
"A381175",
"A381176"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:05:55 | oeisdata/seq/A381/A381176.seq | bdecf2c3dbb6c008deb79cad4d4d4c2a |
A381177 | E.g.f. A(x) satisfies A(x) = 1/( 1 - A(x) * sinh(x * A(x)) ). | [
"1",
"1",
"6",
"73",
"1352",
"33861",
"1072000",
"41083477",
"1849680768",
"95708731945",
"5597075177984",
"365091888890433",
"26281788308598784",
"2069729710424907181",
"177006820644852031488",
"16337090667286093559821",
"1618592591411194127089664",
"171337824188415839421148881",
"19299478529228162963028508672"
] | [
"nonn"
] | 10 | 0 | 3 | [
"A136630",
"A162653",
"A196776",
"A201628",
"A381177",
"A381179"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:05:59 | oeisdata/seq/A381/A381177.seq | cae4e34ef45305fa0aa842eaf0ad9a8b |
A381178 | Irregular triangle read by rows, where row n lists the elements of the multiset of bases and exponents (including exponents = 1) in the prime factorization of n. | [
"1",
"2",
"1",
"3",
"2",
"2",
"1",
"5",
"1",
"1",
"2",
"3",
"1",
"7",
"2",
"3",
"2",
"3",
"1",
"1",
"2",
"5",
"1",
"11",
"1",
"2",
"2",
"3",
"1",
"13",
"1",
"1",
"2",
"7",
"1",
"1",
"3",
"5",
"2",
"4",
"1",
"17",
"1",
"2",
"2",
"3",
"1",
"19",
"1",
"2",
"2",
"5",
"1",
"1",
"3",
"7",
"1",
"1",
"2",
"11",
"1",
"23",
"1",
"2",
"3",
"3",
"2",
"5",
"1",
"1",
"2",
"13",
"3",
"3",
"1",
"2",
"2",
"7",
"1",
"29",
"1",
"1",
"1",
"2",
"3",
"5",
"1",
"31"
] | [
"nonn",
"tabf",
"easy"
] | 31 | 2 | 2 | [
"A000026",
"A001221",
"A008474",
"A035306",
"A081812",
"A381178",
"A381203",
"A381204",
"A381212",
"A381398",
"A381401",
"A381403",
"A381404",
"A381576"
] | null | Paolo Xausa, Feb 27 2025 | 2025-03-01T12:19:05 | oeisdata/seq/A381/A381178.seq | 30f237b82ec19302d699956cd3f6071a |
A381179 | E.g.f. A(x) satisfies A(x) = 1 + sinh(x*A(x)) / A(x). | [
"1",
"1",
"0",
"1",
"8",
"21",
"64",
"1093",
"8448",
"47785",
"654848",
"9402537",
"94222336",
"1264390141",
"23392960512",
"363389219053",
"5722054885376",
"117602664867921",
"2434091053613056",
"47867013812467921",
"1080303165427679232",
"26716998341391367141",
"645003218568158904320",
"16403742152044108508181"
] | [
"nonn"
] | 8 | 0 | 5 | [
"A136630",
"A162653",
"A196776",
"A201628",
"A381177",
"A381179"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:06:03 | oeisdata/seq/A381/A381179.seq | 3520f30cb98e7a73c03b2a345f1ce4f0 |
A381180 | E.g.f. A(x) satisfies A(x) = 1 + sin(x*A(x)) / A(x). | [
"1",
"1",
"0",
"-1",
"-8",
"-19",
"64",
"1091",
"7680",
"-1415",
"-650752",
"-8575865",
"-35559424",
"857890021",
"21380186112",
"203548592651",
"-1615715926016",
"-95486152906639",
"-1599622990659584",
"-1397194164399601",
"657963431581974528",
"18168041375501245021",
"157453907927886725120",
"-6059840564222790027821"
] | [
"sign"
] | 7 | 0 | 5 | [
"A136630",
"A196776",
"A201627",
"A381180",
"A381181",
"A381182"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:06:14 | oeisdata/seq/A381/A381180.seq | 392e5266f4cc4366e178e79ef28eac96 |
A381181 | Expansion of e.g.f. (1/x) * Series_Reversion( x / (1 + sin(x)) ). | [
"1",
"1",
"2",
"5",
"8",
"-79",
"-1584",
"-20539",
"-223616",
"-1855295",
"-1736960",
"435730789",
"14511117312",
"338965239601",
"6202042886144",
"71638247035109",
"-714560796196864",
"-84697775518956799",
"-3650903032332091392",
"-115829159202293866939",
"-2739961030150105333760",
"-29414406825401517785039"
] | [
"sign"
] | 12 | 0 | 3 | [
"A136630",
"A162653",
"A196776",
"A201627",
"A381171",
"A381173",
"A381180",
"A381181",
"A381182"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:06:41 | oeisdata/seq/A381/A381181.seq | 6c5fb9d1d38eb252be741a8cb7aeebbb |
A381182 | E.g.f. A(x) satisfies A(x) = 1/( 1 - A(x) * sin(x * A(x)) ). | [
"1",
"1",
"6",
"71",
"1288",
"31661",
"984640",
"37085075",
"1641305472",
"83497838425",
"4801347029504",
"307975150996831",
"21802395720298496",
"1688562016007776261",
"142023935786330431488",
"12892154760586821775019",
"1256251152910271399624704",
"130793914073764385411654321",
"14490427167940362294881615872"
] | [
"nonn"
] | 9 | 0 | 3 | [
"A136630",
"A196776",
"A201627",
"A381180",
"A381181",
"A381182"
] | null | Seiichi Manyama, Feb 16 2025 | 2025-02-16T10:06:36 | oeisdata/seq/A381/A381182.seq | f2f924cf785e61bbfac4b148f90de50f |
A381183 | a(n) = the smallest positive integer that produces a product that contains the digit 2 when multiplied by 2 at most n times, and where a further multiplication by 2 produces a number that does not contain the digit 2. Set a(n) = -1 if no such number exists. | [
"2",
"1",
"6",
"31",
"128",
"64",
"516",
"331",
"814",
"1607",
"4107",
"10158",
"10258",
"5129",
"10283",
"12819",
"25633",
"28141",
"16163",
"51404",
"80134",
"80864",
"40633",
"80216",
"40108",
"128129",
"250627",
"160626",
"80313",
"125641",
"208141",
"383814",
"391628",
"195814",
"156766",
"196314",
"391563",
"490641",
"806166",
"785313",
"628222",
"314111",
"625322",
"312661",
"1563305",
"2630104",
"1315052",
"657526",
"328763",
"1643815"
] | [
"nonn",
"base"
] | 24 | 0 | 1 | [
"A011532",
"A378138",
"A381087",
"A381183"
] | null | Michael De Vlieger and Scott R. Shannon, Feb 16 2025 | 2025-02-23T09:32:00 | oeisdata/seq/A381/A381183.seq | 3f2cacb9ac52abb9c3455e91e570641d |
A381184 | a(n) = [(x*y*z*u)^n] 1/((1-(x+y+z+u))*(1-x*y-z*u)). | [
"1",
"30",
"2958",
"428652",
"72819090",
"13516242348",
"2655799814220",
"543000625464600",
"114327634610709630",
"24620695529789323140",
"5397810728037535659852",
"1200730183508291762472120",
"270334385874587473289188884",
"61483631908884909800347922616",
"14105087055649813954756928131800"
] | [
"nonn"
] | 9 | 0 | 2 | [
"A006134",
"A381184"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:38:38 | oeisdata/seq/A381/A381184.seq | 9f0c1f7e0f24be63748582e7e22af116 |
A381185 | a(n) = numerator( [x^n] hypergeom([1/4, 3/4], [1], 2^6*x/3^2)/sqrt(1 - 4*x) ). | [
"1",
"10",
"374",
"15484",
"230210",
"10919020",
"1635492740",
"9461595400",
"169793701330",
"253354748427220",
"4762913165558548",
"272892459138645320",
"15830057357705343116",
"309116222832740182552",
"18252959497023816606200",
"3254657058859020013332688",
"7203918574814465440160390",
"1297593844520826560448239324"
] | [
"nonn",
"frac"
] | 14 | 0 | 2 | [
"A381185",
"A381186"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:38:31 | oeisdata/seq/A381/A381185.seq | 9359b9194be9dd45acc36d28ae172788 |
A381186 | a(n) = denominator( [x^n] hypergeom([1/4, 3/4], [1], 2^6*x/3^2)/sqrt(1 - 4*x) ). | [
"1",
"3",
"27",
"243",
"729",
"6561",
"177147",
"177147",
"531441",
"129140163",
"387420489",
"3486784401",
"31381059609",
"94143178827",
"847288609443",
"22876792454961",
"7625597484987",
"205891132094649",
"50031545098999707",
"150094635296999121",
"1350851717672992089",
"1350851717672992089",
"4052555153018976267"
] | [
"nonn",
"frac"
] | 11 | 0 | 2 | [
"A381185",
"A381186"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:38:21 | oeisdata/seq/A381/A381186.seq | fa85d9f7eebb2b4fda8253fcd1dd64a8 |
A381187 | Triangle T(n,k) read by rows whose n-th row is the lexicographically first n-tuple of ordered positive integers with sum A380887(n) and product A380887(n) * 100^(n-1). | [
"1",
"200",
"200",
"150",
"175",
"200",
"125",
"160",
"175",
"184",
"125",
"125",
"160",
"165",
"184",
"125",
"125",
"144",
"150",
"160",
"160",
"125",
"125",
"128",
"144",
"150",
"150",
"150",
"110",
"125",
"125",
"125",
"128",
"150",
"150",
"176",
"125",
"125",
"125",
"125",
"128",
"128",
"132",
"150",
"150",
"120",
"120",
"125",
"125",
"125",
"125",
"128",
"128",
"150",
"150"
] | [
"tabl",
"nonn"
] | 26 | 1 | 2 | [
"A380887",
"A381187"
] | null | Markus Sigg, Feb 16 2025 | 2025-03-28T14:13:09 | oeisdata/seq/A381/A381187.seq | 3f434a6dcff98a2a07f98b5b092f08ea |
A381188 | Number of connected minimal dominating sets in the n X n queen graph. | [
"1",
"4",
"13",
"92",
"1359"
] | [
"nonn",
"more"
] | 5 | 1 | 2 | null | null | Eric W. Weisstein, Feb 16 2025 | 2025-02-16T10:06:51 | oeisdata/seq/A381/A381188.seq | 4b30570fa0ca981de679acfe6e6fc171 |
A381189 | Ulam numbers that are squarefree semiprimes. | [
"6",
"26",
"38",
"57",
"62",
"69",
"77",
"82",
"87",
"106",
"145",
"155",
"177",
"206",
"209",
"219",
"221",
"253",
"309",
"319",
"339",
"341",
"358",
"382",
"451",
"485",
"497",
"502",
"566",
"685",
"695",
"734",
"781",
"849",
"866",
"893",
"905",
"949",
"1018",
"1037",
"1079",
"1081",
"1101",
"1157",
"1167",
"1169",
"1186",
"1191",
"1257",
"1313",
"1355",
"1387",
"1389"
] | [
"nonn"
] | 10 | 1 | 1 | [
"A002858",
"A006881",
"A068820",
"A378795",
"A379162",
"A379532",
"A381189"
] | null | Massimo Kofler, Feb 16 2025 | 2025-03-02T23:54:43 | oeisdata/seq/A381/A381189.seq | cccb5174fe1e3a0cb58de18284fafa81 |
A381190 | Number of connected minimal dominating sets in the n-trapezohedral graph. | [
"6",
"16",
"30",
"36",
"70",
"96",
"144",
"220",
"308",
"456",
"650"
] | [
"nonn",
"more"
] | 4 | 3 | 1 | null | null | Eric W. Weisstein, Feb 16 2025 | 2025-02-16T10:06:46 | oeisdata/seq/A381/A381190.seq | e9dc952644272281c9ad93f69566a05a |
A381191 | Order of the minimal polynomial for the n-th smallest Pisot number. | [
"3",
"4",
"5",
"3",
"6",
"5",
"7",
"6",
"5",
"8"
] | [
"nonn",
"more"
] | 6 | 1 | 1 | null | null | Eric W. Weisstein, Feb 16 2025 | 2025-02-16T17:53:20 | oeisdata/seq/A381/A381191.seq | fff7584d2ff3ba4637b87d5426e0d666 |
A381192 | Irregular triangle read by rows. Properly color the vertices of a simple labeled graph on [n] using exactly n colors c_1<c_2<...<c_n (in other words, use each color exactly once). Orient the edges according to the strict order on the colors. T(n,k) is the number of such graphs with exactly k descents, n>=0, 0<=k<=binomial(n,2). | [
"1",
"1",
"3",
"1",
"21",
"19",
"7",
"1",
"315",
"516",
"419",
"208",
"65",
"12",
"1",
"9765",
"24186",
"31445",
"27488",
"17538",
"8420",
"3050",
"816",
"153",
"18",
"1",
"615195",
"2080323",
"3769767",
"4754751",
"4592847",
"3555479",
"2257723",
"1188595",
"519745",
"187705",
"55237",
"12941",
"2325",
"301",
"25",
"1"
] | [
"nonn",
"tabf"
] | 14 | 0 | 3 | [
"A005329",
"A011266",
"A381058",
"A381102",
"A381192"
] | null | Geoffrey Critzer, Feb 16 2025 | 2025-02-24T19:41:40 | oeisdata/seq/A381/A381192.seq | 89ecf3fa35bd791ede35ce52f45e4387 |
A381193 | a(n) = (3*n-1)*(n^4-18*n^3+179*n^2-582*n+720)/120. | [
"5",
"6",
"12",
"33",
"77",
"153",
"274",
"460",
"741",
"1160",
"1776",
"2667",
"3933",
"5699",
"8118",
"11374",
"15685",
"21306",
"28532",
"37701",
"49197",
"63453",
"80954",
"102240",
"127909",
"158620",
"195096",
"238127",
"288573",
"347367",
"415518",
"494114",
"584325",
"687406",
"804700",
"937641",
"1087757",
"1256673",
"1446114"
] | [
"nonn",
"easy"
] | 19 | 1 | 1 | null | null | Eric W. Weisstein, Feb 16 2025 | 2025-03-03T05:18:07 | oeisdata/seq/A381/A381193.seq | a99ba0710096c45ee775eb08dfc2974d |
A381194 | Number of equal-length matchings of 2n uniformly spaced points on a circle. | [
"1",
"3",
"3",
"9",
"5",
"17",
"7",
"33",
"15",
"49",
"11",
"113",
"13",
"153",
"57",
"321",
"17",
"617",
"19",
"1153",
"165",
"2089",
"23",
"4577",
"85",
"8241",
"555",
"16737",
"29",
"34049",
"31",
"66177",
"2109",
"131137",
"377",
"267521",
"37",
"524361",
"8265",
"1051393",
"41",
"2114081",
"43",
"4198561",
"33945",
"8388697",
"47",
"16851905",
"427",
"33556689"
] | [
"nonn"
] | 20 | 1 | 2 | null | null | Jerrold Grossman, Feb 16 2025 | 2025-04-13T01:47:26 | oeisdata/seq/A381/A381194.seq | a7ad88224b508e8aa71ee3e852385c41 |
A381195 | Expansion of g.f. (1 - sqrt(1 - 1728*x))/(864*x). | [
"1",
"432",
"373248",
"403107840",
"487599243264",
"631928619270144",
"857978513934778368",
"1204601833564428828672",
"1734626640332777513287680",
"2547819609320783611516944384",
"3802273336964543978787469000704",
"5749037285490390495926653129064448",
"8788066841328079995004188536982208512"
] | [
"nonn"
] | 11 | 0 | 2 | [
"A009971",
"A277757",
"A381195"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:38:13 | oeisdata/seq/A381/A381195.seq | cf19b3d136993d20388af1dcb57267e9 |
A381196 | Stellated octagon numbers: a(n) = 20*n^2 + 8*n + 1. | [
"1",
"29",
"97",
"205",
"353",
"541",
"769",
"1037",
"1345",
"1693",
"2081",
"2509",
"2977",
"3485",
"4033",
"4621",
"5249",
"5917",
"6625",
"7373",
"8161",
"8989",
"9857",
"10765",
"11713",
"12701",
"13729",
"14797",
"15905",
"17053",
"18241",
"19469",
"20737",
"22045",
"23393",
"24781",
"26209",
"27677",
"29185",
"30733",
"32321",
"33949"
] | [
"nonn",
"easy"
] | 36 | 0 | 2 | [
"A000217",
"A001844",
"A016742",
"A016814",
"A168668",
"A195162",
"A381196"
] | null | Aaron David Fairbanks, Feb 16 2025 | 2025-03-05T20:44:00 | oeisdata/seq/A381/A381196.seq | af3d26df6d4fab6ecb1fcfb50eb4e4a8 |
A381197 | a(n) = numerator( [(x*y*z*u)^n] 1/sqrt(1 - (x + y + z + u*(x*y + x*z + y*z))) ). | [
"1",
"9",
"1575",
"107415",
"143918775",
"13539797271",
"5492167201521",
"586937023583625",
"4173054453859037175",
"477630312182609961375",
"223908157536370130248425",
"26751307348701533866638825",
"51959852697049291288154030625",
"6393039919009116988875533492625",
"3182668486503393355366954041669375"
] | [
"nonn",
"frac"
] | 10 | 0 | 2 | [
"A268554",
"A381197",
"A381198"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:38:04 | oeisdata/seq/A381/A381197.seq | 37f612d8ec6b54d3d588edf581507320 |
A381198 | a(n) = denominator( [(x*y*z*u)^n] 1/sqrt(1 - (x + y + z + u*(x*y + x*z + y*z))) ). | [
"1",
"4",
"64",
"256",
"16384",
"65536",
"1048576",
"4194304",
"1073741824",
"4294967296",
"68719476736",
"274877906944",
"17592186044416",
"70368744177664",
"1125899906842624",
"4503599627370496",
"4611686018427387904",
"18446744073709551616",
"295147905179352825856",
"1180591620717411303424",
"75557863725914323419136"
] | [
"nonn",
"frac"
] | 13 | 0 | 2 | [
"A268554",
"A381197",
"A381198"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:37:59 | oeisdata/seq/A381/A381198.seq | 442889491fd973108566f3f6544f74d7 |
A381199 | a(n) = (4*n)!/((n!)^2*(2*n)!)*Sum_{k=0..n} binomial(n,k)^2*binomial(2*k,k). | [
"1",
"36",
"6300",
"1718640",
"575675100",
"216636756336",
"87874675224336",
"37563969509352000",
"16692217815436148700",
"7642084994921759382000",
"3582530520581922083974800",
"1712083670316898167464884800",
"831357643152788660610464490000",
"409154554816583487288034143528000",
"203690783136217174743485058666840000"
] | [
"nonn"
] | 12 | 0 | 2 | [
"A000897",
"A000984",
"A001044",
"A002893",
"A007318",
"A008459",
"A010050",
"A100733",
"A381199"
] | null | Stefano Spezia, Feb 16 2025 | 2025-02-19T13:37:51 | oeisdata/seq/A381/A381199.seq | 66ad963126c263201f20edaf2cd17e27 |
A381200 | Numbers k such that (49^k - 2^k)/47 is prime. | [
"3",
"5",
"29",
"89",
"35279"
] | [
"nonn",
"hard",
"more"
] | 6 | 1 | 1 | [
"A062587",
"A062589",
"A127996",
"A127997",
"A128344",
"A204940",
"A217320",
"A225807",
"A229542",
"A375161",
"A375236",
"A377031",
"A381200"
] | null | Robert Price, Feb 16 2025 | 2025-02-16T22:38:23 | oeisdata/seq/A381/A381200.seq | d2cb74f5f3812386432dd2aed4a0c6ed |
A381201 | a(n) is the product of the elements of the set of bases and exponents in the prime factorization of n. | [
"1",
"2",
"3",
"2",
"5",
"6",
"7",
"6",
"6",
"10",
"11",
"6",
"13",
"14",
"15",
"8",
"17",
"6",
"19",
"10",
"21",
"22",
"23",
"6",
"10",
"26",
"3",
"14",
"29",
"30",
"31",
"10",
"33",
"34",
"35",
"6",
"37",
"38",
"39",
"30",
"41",
"42",
"43",
"22",
"30",
"46",
"47",
"24",
"14",
"10",
"51",
"26",
"53",
"6",
"55",
"42",
"57",
"58",
"59",
"30",
"61",
"62",
"42",
"12",
"65",
"66",
"67",
"34",
"69",
"70"
] | [
"nonn",
"easy"
] | 14 | 1 | 2 | [
"A000026",
"A336965",
"A381201",
"A381202",
"A381203",
"A381204",
"A381205"
] | null | Paolo Xausa, Feb 16 2025 | 2025-02-18T18:57:06 | oeisdata/seq/A381/A381201.seq | c8a21e4ecf02a27413c6baafbefdf202 |
A381202 | a(n) is the sum of the elements of the set of bases and exponents (including exponents = 1) in the prime factorization of n. | [
"0",
"3",
"4",
"2",
"6",
"6",
"8",
"5",
"5",
"8",
"12",
"6",
"14",
"10",
"9",
"6",
"18",
"6",
"20",
"8",
"11",
"14",
"24",
"6",
"7",
"16",
"3",
"10",
"30",
"11",
"32",
"7",
"15",
"20",
"13",
"5",
"38",
"22",
"17",
"11",
"42",
"13",
"44",
"14",
"11",
"26",
"48",
"10",
"9",
"8",
"21",
"16",
"54",
"6",
"17",
"13",
"23",
"32",
"60",
"11",
"62",
"34",
"13",
"8",
"19",
"17",
"68",
"20",
"27",
"15",
"72",
"5"
] | [
"nonn",
"easy"
] | 12 | 1 | 2 | [
"A008474",
"A338038",
"A381201",
"A381202",
"A381203",
"A381204",
"A381205"
] | null | Paolo Xausa, Feb 16 2025 | 2025-02-18T18:57:15 | oeisdata/seq/A381/A381202.seq | 8a8392dc3d714b794ae842cc9e648fda |
A381203 | a(n) is the lcm of the elements of the set of bases and exponents in the prime factorization of n. | [
"2",
"3",
"2",
"5",
"6",
"7",
"6",
"6",
"10",
"11",
"6",
"13",
"14",
"15",
"4",
"17",
"6",
"19",
"10",
"21",
"22",
"23",
"6",
"10",
"26",
"3",
"14",
"29",
"30",
"31",
"10",
"33",
"34",
"35",
"6",
"37",
"38",
"39",
"30",
"41",
"42",
"43",
"22",
"30",
"46",
"47",
"12",
"14",
"10",
"51",
"26",
"53",
"6",
"55",
"42",
"57",
"58",
"59",
"30",
"61",
"62",
"42",
"6",
"65",
"66",
"67",
"34",
"69",
"70",
"71"
] | [
"nonn",
"easy"
] | 10 | 2 | 1 | [
"A381201",
"A381202",
"A381203",
"A381204",
"A381205",
"A381213"
] | null | Paolo Xausa, Feb 17 2025 | 2025-02-18T18:57:34 | oeisdata/seq/A381/A381203.seq | ae4f2ef509fc9c23df95d505f68069a1 |
A381204 | a(n) is the gcd of the elements of the set of bases and exponents in the prime factorization of n. | [
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"3",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"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",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1"
] | [
"nonn",
"easy"
] | 13 | 2 | 3 | [
"A368107",
"A381201",
"A381202",
"A381203",
"A381204",
"A381205"
] | null | Paolo Xausa, Feb 17 2025 | 2025-02-21T16:46:51 | oeisdata/seq/A381/A381204.seq | 6e22eceefc623c12fb50cfda0dec3c0b |
A381205 | a(n) is the cardinality of the set of bases and exponents (including exponents = 1) in the prime factorization of n. | [
"0",
"2",
"2",
"1",
"2",
"3",
"2",
"2",
"2",
"3",
"2",
"3",
"2",
"3",
"3",
"2",
"2",
"3",
"2",
"3",
"3",
"3",
"2",
"3",
"2",
"3",
"1",
"3",
"2",
"4",
"2",
"2",
"3",
"3",
"3",
"2",
"2",
"3",
"3",
"4",
"2",
"4",
"2",
"3",
"4",
"3",
"2",
"4",
"2",
"3",
"3",
"3",
"2",
"3",
"3",
"4",
"3",
"3",
"2",
"4",
"2",
"3",
"4",
"2",
"3",
"4",
"2",
"3",
"3",
"4",
"2",
"2",
"2",
"3",
"4",
"3",
"3",
"4",
"2",
"4",
"2",
"3",
"2",
"4",
"3",
"3",
"3",
"4",
"2",
"4"
] | [
"nonn",
"easy"
] | 18 | 1 | 2 | [
"A051674",
"A381201",
"A381202",
"A381203",
"A381204",
"A381205",
"A381212"
] | null | Paolo Xausa, Feb 17 2025 | 2025-02-22T09:57:14 | oeisdata/seq/A381/A381205.seq | dfe3c70f0106bf1a56d6716325c86690 |
A381206 | Expansion of e.g.f. 1/(1 - x*cosh(x))^2. | [
"1",
"2",
"6",
"30",
"192",
"1450",
"12960",
"133574",
"1550976",
"20055186",
"285903360",
"4452231982",
"75186726912",
"1368588922298",
"26709799753728",
"556339845854550",
"12318065768693760",
"288894650033594914",
"7154212267816648704",
"186545064693433665854",
"5108590743587243950080"
] | [
"nonn"
] | 10 | 0 | 2 | [
"A185951",
"A205571",
"A381206",
"A381207"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:12 | oeisdata/seq/A381/A381206.seq | 27955d79a28a586caa4a072b304b4c22 |
A381207 | Expansion of e.g.f. 1/(1 - x*cosh(x))^3. | [
"1",
"3",
"12",
"69",
"504",
"4335",
"43200",
"490161",
"6220032",
"87242427",
"1340305920",
"22375475133",
"403237638144",
"7801208775399",
"161245892161536",
"3545854432602345",
"82653484859228160",
"2035605515838402291",
"52814589875313573888",
"1439814136866851346357",
"41145786213980645621760"
] | [
"nonn"
] | 12 | 0 | 2 | [
"A185951",
"A205571",
"A377530",
"A381206",
"A381207",
"A381209",
"A381210",
"A381211"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:15 | oeisdata/seq/A381/A381207.seq | 012cbef07ca6700ddfa81052305977a4 |
A381208 | Expansion of e.g.f. 1/(1 - x*cos(x))^2. | [
"1",
"2",
"6",
"18",
"48",
"10",
"-1440",
"-17654",
"-153216",
"-1003950",
"-2787840",
"58057538",
"1483941888",
"22381115354",
"245730121728",
"1455189928890",
"-18135147970560",
"-856283065534046",
"-19218870434267136",
"-306007541260257422",
"-2933654664287354880",
"20552099782407258282",
"1938717354581701951488"
] | [
"sign"
] | 10 | 0 | 2 | [
"A185951",
"A352252",
"A381208",
"A381209"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:19 | oeisdata/seq/A381/A381208.seq | cf5cc6df1ad8fe215fcf13810931c469 |
A381209 | Expansion of e.g.f. 1/(1 - x*cos(x))^3. | [
"1",
"3",
"12",
"51",
"216",
"735",
"0",
"-39081",
"-575232",
"-6047973",
"-48314880",
"-189159333",
"3046957056",
"99745485879",
"1789140627456",
"23433663134655",
"185580069027840",
"-1250544374605389",
"-94781673979379712",
"-2543434372808424957",
"-47763303489939701760",
"-586864592847636893937"
] | [
"sign"
] | 12 | 0 | 2 | [
"A185951",
"A352252",
"A377530",
"A381207",
"A381208",
"A381209",
"A381210",
"A381211"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:26 | oeisdata/seq/A381/A381209.seq | c188bb59c0ee2c394e3113eb4e4d160e |
A381210 | Expansion of e.g.f. 1/(1 - sinh(x))^3. | [
"1",
"3",
"12",
"63",
"408",
"3123",
"27552",
"275103",
"3065088",
"37682883",
"506606592",
"7392091743",
"116329479168",
"1963781841843",
"35395627487232",
"678401549017983",
"13776623985819648",
"295481239628640003",
"6674320861079273472",
"158364407589097613823",
"3937958237874411798528"
] | [
"nonn"
] | 10 | 0 | 2 | [
"A136630",
"A377530",
"A381207",
"A381209",
"A381210",
"A381211"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:22 | oeisdata/seq/A381/A381210.seq | cb036015b561e5ceb6d03d5b13afb21f |
A381211 | Expansion of e.g.f. 1/(1 - sin(x))^3. | [
"1",
"3",
"12",
"57",
"312",
"1923",
"13152",
"98697",
"805632",
"7102563",
"67233792",
"679970937",
"7315786752",
"83421156003",
"1004860895232",
"12749105088777",
"169926064668672",
"2373678328434243",
"34676591077097472",
"528758667342524217",
"8400613520498491392",
"138830752520282729283"
] | [
"nonn"
] | 11 | 0 | 2 | [
"A136630",
"A185690",
"A377530",
"A381207",
"A381209",
"A381210",
"A381211"
] | null | Seiichi Manyama, Feb 17 2025 | 2025-02-17T08:18:31 | oeisdata/seq/A381/A381211.seq | 0661966fef3496d839059d94db61951d |
A381212 | a(n) is the smallest element of the set of bases and exponents (including exponents = 1) in the prime factorization of n. | [
"1",
"1",
"2",
"1",
"1",
"1",
"2",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"3",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"3",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1",
"1"
] | [
"nonn",
"easy"
] | 12 | 2 | 3 | [
"A001694",
"A081812",
"A288636",
"A331048",
"A381201",
"A381202",
"A381203",
"A381204",
"A381205",
"A381212",
"A381214"
] | null | Paolo Xausa, Feb 19 2025 | 2025-03-05T05:36:43 | oeisdata/seq/A381/A381212.seq | ee53d9b2439bd601f713ad183f74fb6d |
A381213 | Numbers k such that A381201(k) != A381203(k). | [
"16",
"48",
"64",
"80",
"112",
"144",
"162",
"176",
"192",
"208",
"240",
"256",
"272",
"304",
"320",
"324",
"336",
"368",
"400",
"432",
"448",
"464",
"496",
"528",
"560",
"576",
"592",
"624",
"648",
"656",
"688",
"704",
"720",
"729",
"752",
"768",
"784",
"810",
"816",
"832",
"848",
"880",
"912",
"944",
"960",
"976",
"1008",
"1024",
"1040",
"1072",
"1088",
"1104"
] | [
"nonn",
"easy"
] | 6 | 1 | 1 | [
"A381201",
"A381203",
"A381213"
] | null | Paolo Xausa, Feb 17 2025 | 2025-02-18T18:58:47 | oeisdata/seq/A381/A381213.seq | 7c403e448de7d5b12a4ae6ecc86fe016 |
A381214 | a(n) is the difference between the largest and smallest element of the set of bases and exponents (including exponents = 1) in the prime factorization of n. | [
"1",
"2",
"0",
"4",
"2",
"6",
"1",
"1",
"4",
"10",
"2",
"12",
"6",
"4",
"2",
"16",
"2",
"18",
"4",
"6",
"10",
"22",
"2",
"3",
"12",
"0",
"6",
"28",
"4",
"30",
"3",
"10",
"16",
"6",
"1",
"36",
"18",
"12",
"4",
"40",
"6",
"42",
"10",
"4",
"22",
"46",
"3",
"5",
"4",
"16",
"12",
"52",
"2",
"10",
"6",
"18",
"28",
"58",
"4",
"60",
"30",
"6",
"4",
"12",
"10",
"66",
"16",
"22",
"6",
"70",
"1",
"72",
"36",
"4",
"18"
] | [
"nonn",
"easy"
] | 13 | 2 | 2 | [
"A046665",
"A051674",
"A081812",
"A381212",
"A381214",
"A381215"
] | null | Paolo Xausa, Feb 19 2025 | 2025-02-21T09:31:16 | oeisdata/seq/A381/A381214.seq | da5693f8794654501e2f4923b579839a |
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