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348
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score
int64
1
2.35k
offset_a
int64
-14,827
666,262,453B
offset_b
int64
0
635M
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1999-12-11 03:00:00
2025-07-19 00:40:46
filename
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A380304
a(n) = sigma(A380303(n)).
[ "1", "12", "18", "12", "24", "24", "31", "18", "42", "32", "24", "60", "31", "42", "56", "72", "32", "48", "54", "48", "60", "56", "90", "42", "96", "84", "72", "48", "72", "98", "54", "120", "72", "120", "80", "90", "60", "168", "96", "104", "84", "144", "96", "144", "72", "114", "140", "96", "168", "80", "84", "224", "108", "132", "120", "180", "90", "234", "168", "128", "144", "120", "252", "98", "156", "216", "104", "192", "108", "280", "216", "152", "248", "114", "240", "144", "182", "180", "144", "360", "168", "224", "156", "312", "128", "252", "132", "336", "240", "270", "288", "140", "336", "192" ]
[ "nonn" ]
11
1
2
[ "A000203", "A206036", "A206421", "A211656", "A241480", "A241481", "A241625", "A380303", "A380304" ]
null
Max Alekseyev, Jan 19 2025
2025-01-22T06:04:20
oeisdata/seq/A380/A380304.seq
4ef8fd77b5b3bf26ccad1c06283eb11e
A380305
Triangle read by rows: T(n,k) = (n - floor((n - k)/k)) mod k, for 0 < k <= n.
[ "0", "0", "0", "0", "1", "0", "0", "1", "1", "0", "0", "0", "2", "1", "0", "0", "0", "2", "2", "1", "0", "0", "1", "0", "3", "2", "1", "0", "0", "1", "1", "3", "3", "2", "1", "0", "0", "0", "1", "0", "4", "3", "2", "1", "0", "0", "0", "2", "1", "4", "4", "3", "2", "1", "0", "0", "1", "0", "2", "0", "5", "4", "3", "2", "1", "0", "0", "1", "0", "2", "1", "5", "5", "4", "3", "2", "1", "0", "0", "0", "1", "3", "2", "0", "6", "5", "4", "3", "2", "1", "0" ]
[ "nonn", "tabl" ]
18
1
13
[ "A048158", "A375595", "A378275", "A380153", "A380305" ]
null
Lechoslaw Ratajczak, Jan 19 2025
2025-02-05T13:22:01
oeisdata/seq/A380/A380305.seq
b15dac502f976496857e47e0f9761484
A380306
Irregular triangle read by rows: T(n,k) is the number of rooted binary normal unlabeled galled trees with n leaves and exactly k galls, 0 <= k <= floor((n-1)/2).
[ "1", "1", "1", "1", "2", "4", "3", "15", "2", "6", "48", "18", "11", "148", "107", "6", "23", "435", "528", "78", "46", "1250", "2295", "661", "19", "98", "3512", "9185", "4356", "346", "207", "9726", "34503", "24564", "3776", "67", "451", "26587", "123612", "123825", "31289", "1543", "983", "71975", "426218", "574149", "216501", "20720", "246" ]
[ "nonn", "tabf" ]
4
1
5
[ "A001190", "A380211", "A380256", "A380306" ]
null
Noah A Rosenberg, Jan 19 2025
2025-02-01T23:12:16
oeisdata/seq/A380/A380306.seq
6e8f8b3dee079c55b5f5774fb9150146
A380307
Expansion of e.g.f. exp( (1+5*x)^(1/5) - 1 ).
[ "1", "1", "-3", "25", "-335", "6177", "-144947", "4128937", "-138327615", "5327738497", "-231899041475", "11255588133945", "-602683483719503", "35288931375293857", "-2242963870471014963", "153791777744471484745", "-11314787069889491407103", "889087243145447511507969", "-74312052321224600661026051" ]
[ "sign" ]
15
0
3
[ "A000110", "A000806", "A028575", "A380208", "A380307" ]
null
Seiichi Manyama, Jan 20 2025
2025-01-21T05:00:16
oeisdata/seq/A380/A380307.seq
cf154fc79dab06516f738285c9a670ea
A380308
Expansion of e.g.f. exp( 1 - 1/(1-2*x)^(1/2) ).
[ "1", "-1", "-2", "-7", "-35", "-226", "-1769", "-16003", "-159998", "-1669645", "-16203509", "-85724926", "2606965153", "154547040023", "6047755681150", "217270016433329", "7721994442008061", "279057037146008702", "10378357435103977207", "399487271346562859045", "15957215240554330744066" ]
[ "sign" ]
18
0
3
[ "A000587", "A001147", "A145561", "A380308", "A380309", "A380310" ]
null
Seiichi Manyama, Jan 20 2025
2025-01-21T05:00:06
oeisdata/seq/A380/A380308.seq
7c10bd29cdf4c1a6b7f2865b50de16df
A380309
Expansion of e.g.f. exp( 1 - 1/(1-3*x)^(1/3) ).
[ "1", "-1", "-3", "-17", "-143", "-1601", "-22419", "-377217", "-7415743", "-166854657", "-4229195779", "-119251176881", "-3702809175823", "-125546570425537", "-4615357640315603", "-182855338776726561", "-7766868454872857599", "-352082642456714366977", "-16965451818345573907843" ]
[ "sign" ]
18
0
3
[ "A000587", "A007559", "A015735", "A145561", "A380308", "A380309", "A380310" ]
null
Seiichi Manyama, Jan 20 2025
2025-01-21T05:00:00
oeisdata/seq/A380/A380309.seq
634754c9754ab919ba0c874a119fcb87
A380310
Expansion of e.g.f. exp( 1 - 1/(1-5*x)^(1/5) ).
[ "1", "-1", "-5", "-49", "-719", "-14077", "-344909", "-10152829", "-349045535", "-13727327833", "-607873987637", "-29931556660105", "-1622308999459631", "-95982568510668373", "-6155361624644676989", "-425321834949751148053", "-31502433469012320013631", "-2489898822489054343250737", "-209178052238110675644666341" ]
[ "sign" ]
18
0
3
[ "A000587", "A008548", "A028575", "A145561", "A380308", "A380309", "A380310" ]
null
Seiichi Manyama, Jan 20 2025
2025-01-21T04:59:56
oeisdata/seq/A380/A380310.seq
325d1da7096a90f5f0a335a81115cc5f
A380311
Partial sums of A377090.
[ "0", "2", "1", "2", "0", "3", "-1", "-7", "-10", "-6", "0", "-5", "-12", "-21", "-13", "-8", "-1", "8", "0", "-10", "-22", "-11", "2", "12", "24", "13", "0", "-15", "-1", "15", "33", "48", "34", "18", "0", "19", "36", "56", "39", "20", "-1", "21", "45", "66", "46", "24", "0", "23", "48", "75", "49", "26", "1", "-26", "0", "28", "58", "29", "-2", "-30", "-60", "-31", "0", "33", "-1", "-33" ]
[ "sign", "look" ]
20
0
2
[ "A377090", "A380311", "A383444" ]
null
Paolo Xausa, Jan 20 2025
2025-05-02T10:34:45
oeisdata/seq/A380/A380311.seq
4646c4558b72fe743efe41e4beaae007
A380312
Primes not reaching 3 under iterations of p -> gpf(2*p-1).
[ "19", "29", "37", "67", "73", "101", "131", "167", "181", "197", "211", "241", "251", "257", "317", "389", "421", "463", "479", "503", "523", "599", "643", "653", "691", "719", "739", "811", "827", "859", "887", "907", "919", "941", "983", "1039", "1061", "1069", "1109", "1117", "1217", "1277", "1283", "1289", "1307", "1361", "1381", "1427", "1429", "1499" ]
[ "easy", "nonn" ]
16
1
1
[ "A006530", "A023583", "A380312" ]
null
Johannes M.V.A. Koelman, Jan 20 2025
2025-01-24T23:20:08
oeisdata/seq/A380/A380312.seq
3a8835c7dec9ce7e272856aec9597bba
A380313
Partial sums of A379057.
[ "0", "4", "-1", "-2", "1", "-5", "-7", "-5", "1", "-2", "-1", "4", "0", "-8", "0", "12", "-1", "-10", "-3", "8", "-6", "-16", "-1", "18", "28", "42", "31", "24", "33", "46", "34", "18", "38", "54", "34", "10", "-5", "-24", "-7", "14", "39", "68", "101", "125", "100", "79", "62", "36", "14", "-4", "14", "36", "62", "39", "12", "-19", "-54", "-93", "-123", "-89", "-59", "-93", "-131", "-160", "-193", "-162" ]
[ "sign", "look" ]
8
0
2
[ "A379057", "A380313" ]
null
Paolo Xausa, Jan 20 2025
2025-01-23T00:25:24
oeisdata/seq/A380/A380313.seq
96018e6d3d8f72c21b96f4c9f74a41dc
A380314
Numerator of sum of reciprocals of all prime divisors of all positive integers <= n.
[ "0", "1", "5", "4", "23", "71", "527", "316", "117", "283", "3183", "5737", "75736", "170777", "186793", "100904", "1730383", "1295397", "24782713", "13522987", "42878411", "91488457", "2113934201", "1149922463", "234446350", "494634185", "169835681", "89698402", "2608690087", "84946052281", "2639797313941", "1370038779503", "1412581913773" ]
[ "nonn", "frac" ]
18
1
3
[ "A000720", "A007947", "A013939", "A024451", "A024924", "A028235", "A284648", "A379367", "A380314", "A380315" ]
null
Ilya Gutkovskiy, Jan 20 2025
2025-01-26T14:52:56
oeisdata/seq/A380/A380314.seq
21b28938a81c0a4c622db9ec41162410
A380315
Denominator of sum of reciprocals of all prime divisors of all positive integers <= n.
[ "1", "2", "6", "3", "15", "30", "210", "105", "35", "70", "770", "1155", "15015", "30030", "30030", "15015", "255255", "170170", "3233230", "1616615", "4849845", "9699690", "223092870", "111546435", "22309287", "44618574", "14872858", "7436429", "215656441", "6469693230", "200560490130", "100280245065", "100280245065" ]
[ "nonn", "frac" ]
10
1
2
[ "A000720", "A007947", "A013939", "A024924", "A028235", "A284650", "A379368", "A379370", "A380314", "A380315" ]
null
Ilya Gutkovskiy, Jan 20 2025
2025-01-26T17:43:42
oeisdata/seq/A380/A380315.seq
6414d17c31e134fb3ddea40fa64ebd5a
A380316
Sphenic numbers that are the sum of two successive sphenics.
[ "385", "555", "759", "897", "935", "957", "1185", "1245", "1265", "1335", "2015", "2037", "2185", "2211", "2261", "2379", "2607", "2821", "2877", "2937", "3059", "3298", "3363", "3434", "3485", "3507", "3538", "3815", "3913", "4029", "4255", "4378", "4433", "4526", "4615", "4738", "4795", "4947", "5181", "5205", "5395", "5405", "5523", "5681", "5829", "5883", "6226" ]
[ "nonn" ]
13
1
1
[ "A001043", "A007304", "A092192", "A380316" ]
null
Massimo Kofler, Jan 20 2025
2025-01-21T11:49:13
oeisdata/seq/A380/A380316.seq
d3ef9ef35f744b6eada813ebf34ad2ca
A380317
The lexicographically earliest sequence of positive numbers which is identical to the run lengths of its first differences.
[ "1", "1", "2", "2", "2", "3", "4", "3", "2", "2", "2", "2", "3", "4", "5", "6", "5", "4", "3", "3", "3", "2", "1", "1", "1", "2", "3", "3", "3", "3", "4", "5", "6", "7", "6", "5", "4", "3", "2", "2", "2", "2", "2", "2", "2", "3", "4", "5", "6", "7", "6", "5", "4", "3", "3", "3", "3", "4", "5", "6", "5", "4", "3", "3", "3", "1", "1", "2", "2", "2", "3", "4", "5", "4", "3", "2", "2", "2", "2", "3", "4", "5", "4", "3", "2", "1", "1" ]
[ "nonn", "nice", "look" ]
23
1
3
[ "A281579", "A281900", "A380317" ]
null
Dominic McCarty, Feb 13 2025
2025-02-18T18:39:08
oeisdata/seq/A380/A380317.seq
40c6032375e144ecc30bc8424fcb5fdd
A380318
Product of the first n perfect powers (A001597).
[ "1", "1", "4", "32", "288", "4608", "115200", "3110400", "99532800", "3583180800", "175575859200", "11236854988800", "910185254092800", "91018525409280000", "11013241574522880000", "1376655196815360000000", "176211865192366080000000", "25374508587700715520000000", "4288291951321420922880000000", "840505222458998500884480000000", "181549128051143676191047680000000" ]
[ "nonn" ]
8
0
3
[ "A000442", "A001044", "A001597", "A002110", "A024923", "A036691", "A076408", "A111059", "A380318" ]
null
Ilya Gutkovskiy, Jan 20 2025
2025-05-03T17:20:39
oeisdata/seq/A380/A380318.seq
ccc95d4f1e8e1c34eeecbaf8deb8f34b
A380319
Smallest prime that is the sum of 2n+1 squares of consecutive odd primes, or 0 if no such prime exists.
[ "83", "373", "1543", "2393", "4723", "10453", "0", "24953", "35323", "0", "56383", "98017", "0", "122701", "238879", "0", "263723", "318181", "0", "486617", "816547", "0", "874487", "817561", "0", "1130957", "1203343", "0", "3110867", "2451637", "1789391", "1987849", "2331379", "0", "2706679", "3124129", "0", "4260437", "4446319", "0" ]
[ "nonn" ]
9
1
1
[ "A001248", "A082244", "A379760", "A380319" ]
null
Michel Marcus, Jan 20 2025
2025-01-20T22:54:29
oeisdata/seq/A380/A380319.seq
5364dba3720843f7fdd27378b2950e42
A380320
First differences of A377092.
[ "1", "-2", "3", "1", "-5", "-1", "-1", "8", "1", "1", "1", "-13", "1", "-2", "-1", "-1", "-1", "21", "-3", "1", "1", "-21", "-1", "-1", "-1", "-1", "-1", "-1", "34", "-5", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "-55", "8", "1", "-2", "-1", "-1", "-1", "-1", "-1", "-1", "-2", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "-1", "89", "-13", "-3" ]
[ "sign" ]
9
0
2
[ "A377092", "A380320" ]
null
Paolo Xausa, Jan 20 2025
2025-01-23T00:25:34
oeisdata/seq/A380/A380320.seq
454edbd36272cf5d9eb9446e9126e7fe
A380321
Partial sums of A377092.
[ "0", "1", "0", "2", "5", "3", "0", "-4", "0", "5", "11", "18", "12", "7", "0", "-8", "-17", "-27", "-16", "-8", "1", "11", "0", "-12", "-25", "-39", "-54", "-70", "-87", "-70", "-58", "-45", "-31", "-16", "0", "18", "37", "57", "78", "100", "123", "147", "172", "198", "225", "253", "226", "207", "189", "169", "148", "126", "103", "79", "54", "28", "0", "-29", "-59", "-90", "-122", "-155" ]
[ "sign" ]
7
0
4
[ "A377092", "A380321" ]
null
Paolo Xausa, Jan 20 2025
2025-01-23T00:26:05
oeisdata/seq/A380/A380321.seq
1dfec92125505b70bb9e44c0b9bc5bde
A380322
a(n) is the sum of exponentially odd divisors of n^2.
[ "1", "3", "4", "11", "6", "12", "8", "43", "31", "18", "12", "44", "14", "24", "24", "171", "18", "93", "20", "66", "32", "36", "24", "172", "131", "42", "274", "88", "30", "72", "32", "683", "48", "54", "48", "341", "38", "60", "56", "258", "42", "96", "44", "132", "186", "72", "48", "684", "351", "393", "72", "154", "54", "822", "72", "344", "80", "90", "60", "264", "62", "96", "248" ]
[ "nonn", "easy", "mult" ]
10
1
2
[ "A000005", "A000203", "A000290", "A005117", "A033634", "A202535", "A268335", "A380322" ]
null
Amiram Eldar, Jan 20 2025
2025-01-21T13:33:24
oeisdata/seq/A380/A380322.seq
20b45bbe86f4a4850194bd3974e21a99
A380323
The number of squares dividing the n-th exponentially odd number.
[ "1", "1", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "2", "1", "2", "1", "1", "1", "3", "1", "1", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "2", "1", "2", "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", "3", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "2", "1" ]
[ "nonn", "easy" ]
8
1
7
[ "A013661", "A046951", "A065463", "A268335", "A380323", "A380324", "A380325" ]
null
Amiram Eldar, Jan 20 2025
2025-01-21T06:33:12
oeisdata/seq/A380/A380323.seq
00432614acf055915ee738728ba8b86e
A380324
The sum of the squares dividing the n-th exponentially odd number.
[ "1", "1", "1", "1", "1", "1", "5", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "5", "1", "10", "1", "1", "1", "21", "1", "1", "1", "1", "1", "1", "5", "1", "1", "1", "1", "1", "1", "1", "10", "1", "5", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "5", "1", "1", "1", "1", "1", "21", "1", "1", "1", "1", "5", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "5" ]
[ "nonn", "easy" ]
7
1
7
[ "A035316", "A268335", "A380323", "A380324", "A380325" ]
null
Amiram Eldar, Jan 20 2025
2025-01-21T18:19:53
oeisdata/seq/A380/A380324.seq
6dd4fa66e4ee1c6199101012159e7c26
A380325
The sum of the square roots of the squares that divide the n-th exponentially odd number.
[ "1", "1", "1", "1", "1", "1", "3", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "3", "1", "4", "1", "1", "1", "7", "1", "1", "1", "1", "1", "1", "3", "1", "1", "1", "1", "1", "1", "1", "4", "1", "3", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "3", "1", "1", "1", "1", "1", "7", "1", "1", "1", "1", "3", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "3", "1" ]
[ "nonn", "easy" ]
8
1
7
[ "A013661", "A065463", "A069290", "A268335", "A330596", "A380323", "A380324", "A380325" ]
null
Amiram Eldar, Jan 20 2025
2025-01-22T03:30:42
oeisdata/seq/A380/A380325.seq
eb0ee5a9022eb3dcd7a1d529d6f58907
A380326
a(n) is the sum of squarefree divisors of the n-th exponentially odd number.
[ "1", "3", "4", "6", "12", "8", "3", "18", "12", "14", "24", "24", "18", "20", "32", "36", "24", "12", "42", "4", "30", "72", "32", "3", "48", "54", "48", "38", "60", "56", "18", "42", "96", "44", "72", "48", "72", "54", "12", "72", "24", "80", "90", "60", "62", "96", "84", "144", "68", "96", "144", "72", "74", "114", "96", "168", "80", "126", "84", "108", "132", "120", "36", "90", "112" ]
[ "nonn", "easy" ]
17
1
2
[ "A005117", "A048250", "A065463", "A268335", "A366439", "A366534", "A366535", "A380326" ]
null
Amiram Eldar, Jan 20 2025
2025-01-21T10:35:37
oeisdata/seq/A380/A380326.seq
7d9561de2fd25db08016f03747372387
A380327
Degeneracy of the n-Mycielski graph.
[ "0", "1", "2", "3", "5", "8", "12", "18", "29", "44", "68", "107", "169", "262", "412", "657", "1027", "1632", "2572", "4104", "6463", "10294", "16413", "25935" ]
[ "nonn", "more" ]
17
1
3
null
null
Eric W. Weisstein, Jan 21 2025
2025-06-11T17:01:54
oeisdata/seq/A380/A380327.seq
c32af93b228c4f67bc504cefa9bce7cd
A380328
2-dense squarefree numbers: Squarefree numbers whose divisors increase by factors of at most 2.
[ "1", "2", "6", "30", "42", "66", "210", "330", "390", "462", "510", "546", "570", "690", "714", "798", "858", "870", "930", "966", "1110", "1122", "1218", "1230", "1254", "1290", "1302", "1410", "1518", "1554", "1590", "1722", "1770", "1806", "1914", "1974", "2046", "2226", "2310", "2442", "2478", "2562", "2706", "2730", "2814", "2838", "2982", "3066", "3102", "3318", "3486", "3498" ]
[ "nonn" ]
28
1
2
[ "A005117", "A005153", "A174973", "A265501", "A267124", "A380328" ]
null
Frank M Jackson, Jan 21 2025
2025-01-25T12:33:42
oeisdata/seq/A380/A380328.seq
4000488f682326a0583f6feeef738073
A380329
a(n) = A151800((n-1)*A151800(n)).
[ "2", "2", "5", "11", "17", "29", "37", "67", "79", "89", "101", "131", "149", "211", "223", "239", "257", "307", "331", "419", "439", "461", "487", "641", "673", "701", "727", "757", "787", "877", "907", "1117", "1151", "1187", "1223", "1259", "1297", "1481", "1523", "1559", "1601", "1721", "1777", "1979", "2027", "2069", "2129", "2441", "2503", "2549", "2609" ]
[ "nonn" ]
16
0
1
[ "A000040", "A151800", "A378135", "A379405", "A380329" ]
null
Clark Kimberling, Jan 21 2025
2025-01-26T21:00:20
oeisdata/seq/A380/A380329.seq
1f4cfda118b4d22fa21aef2a183bda8f
A380330
a(n) = A151800(prime(n)*A151800(n)).
[ "5", "11", "29", "37", "79", "97", "191", "211", "257", "331", "409", "487", "701", "733", "809", "907", "1123", "1163", "1543", "1637", "1693", "1823", "2411", "2591", "2819", "2939", "2999", "3109", "3389", "3511", "4703", "4861", "5077", "5147", "5519", "5591", "6449", "6689", "6857", "7103", "7699", "7789", "8999", "9091", "9277", "9371", "11197" ]
[ "nonn" ]
19
1
1
[ "A000040", "A151800", "A380330" ]
null
Clark Kimberling, Jan 21 2025
2025-03-31T23:09:58
oeisdata/seq/A380/A380330.seq
a9eb1e42feb9eab92f10ce368a36ac94
A380331
a(n) = number of primes < n^4.
[ "0", "0", "6", "22", "54", "114", "210", "357", "564", "847", "1229", "1715", "2334", "3107", "4052", "5191", "6542", "8152", "10022", "12187", "14683", "17531", "20768", "24421", "28546", "33118", "38236", "43934", "50203", "57097", "64683", "72992", "82025", "91932", "102588", "114204", "126726", "140235", "154787", "170426", "187134" ]
[ "nonn" ]
15
0
3
[ "A000040", "A000583", "A000720", "A038107", "A380331" ]
null
Clark Kimberling, Jan 21 2025
2025-01-23T15:34:42
oeisdata/seq/A380/A380331.seq
a9c75f7f30e1ba665fb53883ddcdc98f
A380332
a(n) = number of primes between n^2 and n^4.
[ "0", "0", "4", "18", "48", "105", "199", "342", "546", "825", "1204", "1685", "2300", "3068", "4008", "5143", "6488", "8091", "9956", "12115", "14605", "17446", "20676", "24322", "28441", "33004", "38114", "43805", "50066", "56951", "64529", "72830", "81853", "91751", "102397", "114004", "126516", "140016", "154559", "170186", "186883", "204880", "224009", "244527", "266283", "289506", "314148", "340292", "368114", "397407" ]
[ "nonn" ]
17
0
3
[ "A000040", "A000720", "A038107", "A079648", "A380331", "A380332" ]
null
Clark Kimberling, Jan 26 2025
2025-01-28T00:57:32
oeisdata/seq/A380/A380332.seq
770dd867a88c73265f2b46e2db47d960
A380333
Where prime race 8m+3 vs. 8m+7 is tied.
[ "2", "7", "31", "37", "41", "47", "53", "79", "103", "127", "199", "223", "239", "241", "263", "269", "283", "293", "311", "313", "317", "367", "373", "383", "389", "397", "401", "409", "431", "433", "443", "449", "457", "461", "467", "499", "523", "541", "1039", "1049", "1063", "1069", "1091", "1093", "1097", "1123", "1129", "1163", "1231", "1237", "1249" ]
[ "nonn" ]
4
1
1
[ "A379643", "A379731", "A379989", "A380333" ]
null
Ya-Ping Lu, Jan 21 2025
2025-02-03T23:00:58
oeisdata/seq/A380/A380333.seq
d5f47a8a380041e5166005cecd829b47
A380334
Decimal expansion of the smallest possible average gap for the prime number subsequence P" = A262275.
[ "9", "4", "5", "1", "9", "3", "9", "8", "1", "3", "4", "4", "7", "8", "0", "6", "3", "1", "1", "4", "1", "0", "7", "5", "0", "2", "2", "4", "7", "0", "8", "4", "0", "4", "2", "1", "7", "5", "4", "2", "0", "4", "5", "1", "5", "5", "4", "8", "6", "7", "9", "6", "2", "6", "3", "0", "9", "1", "6", "8", "3", "2", "3", "6", "5", "0", "5", "4", "8", "7", "9", "5", "6", "5", "9", "6", "7", "6", "5", "2", "1", "0", "6", "1", "0", "0", "9", "7", "8", "7", "0", "9", "0", "8", "4", "1", "9", "6", "6" ]
[ "nonn", "cons" ]
32
1
1
[ "A262275", "A338460", "A380334" ]
null
Michael P. May, Jan 21 2025
2025-01-29T16:35:06
oeisdata/seq/A380/A380334.seq
92d59a70bd4563d0ffccfd7675723ab4
A380335
Minimal number of generators of Gamma_0(n).
[ "2", "2", "2", "3", "3", "4", "3", "4", "4", "5", "4", "6", "5", "6", "6", "6", "5", "8", "5", "8", "7", "8", "6", "10", "7", "9", "8", "10", "7", "14", "7", "10", "10", "11", "10", "14", "9", "12", "11", "14", "9", "18", "9", "14", "14", "14", "10", "18", "11", "17", "14", "16", "11", "20", "14", "18", "15", "17", "12", "26", "13", "18", "18", "18", "17", "26", "13", "20", "18", "26", "14", "26", "15", "21", "22", "22", "18", "30" ]
[ "nonn" ]
16
1
1
[ "A001615", "A380335" ]
null
Abouzar Shirazi, Jan 21 2025
2025-01-22T11:41:16
oeisdata/seq/A380/A380335.seq
e8f5c10200d0d8abb180d26c4403a6ae
A380336
Triangular array read by rows. T(n,k) is the number of ways to choose a size k subset S of [n] and form a labeled acyclic digraph on S. Then form another labeled acyclic digraph on [n]-S. For each pair u in S and v in [n]-S add the directed edge u->v or not, n>=0, 0<=k<=n.
[ "1", "1", "1", "3", "4", "3", "25", "36", "36", "25", "543", "800", "864", "800", "543", "29281", "43440", "48000", "48000", "43440", "29281", "3781503", "5621952", "6255360", "6400000", "6255360", "5621952", "3781503", "1138779265", "1694113344", "1888975872", "1946112000", "1946112000", "1888975872", "1694113344", "1138779265" ]
[ "nonn", "tabl" ]
16
0
4
[ "A003024", "A339934", "A380336" ]
null
Geoffrey Critzer, Jan 21 2025
2025-01-23T00:22:52
oeisdata/seq/A380/A380336.seq
8f80c9e890a2572d1abc81f570530696
A380337
Number of perfect powers (in A001597) that do not exceed primorial A002110(n).
[ "1", "1", "2", "7", "19", "63", "208", "802", "3344", "15576", "82368", "453834", "2743903", "17510668", "114616907", "785002449", "5711892439", "43861741799", "342522899289", "2803468693325", "23621594605383", "201819398349092", "1793794228847381", "16342173067958793", "154171432351500060", "1518411003599957803" ]
[ "nonn" ]
22
0
3
[ "A001597", "A002110", "A070228", "A070428", "A380254", "A380337" ]
null
Michael De Vlieger, Jan 21 2025
2025-01-23T15:34:29
oeisdata/seq/A380/A380337.seq
e5ebd97f012aecac63e7b60ef86c68c0
A380338
Expansion of e.g.f. log(1 - x * log(1 - x)).
[ "0", "0", "2", "3", "-4", "-30", "54", "1260", "3856", "-36288", "-279000", "2970000", "56725008", "109343520", "-5495740992", "-26086263840", "1293641890560", "21771049466880", "-45508965806592", "-4589738336217600", "10493846174810880", "2423866077943511040", "34328754265480012800", "-358930542362135546880" ]
[ "sign" ]
16
0
3
[ "A001048", "A052804", "A052858", "A089064", "A375684", "A380338", "A380339" ]
null
Seiichi Manyama, Jan 21 2025
2025-01-22T06:39:38
oeisdata/seq/A380/A380338.seq
ca7bf54b742eb064307ce3410cd16cf6
A380339
Expansion of e.g.f. log(1 - x^2/2 * log(1 - x)).
[ "0", "0", "0", "3", "6", "20", "0", "-126", "-1260", "3240", "108360", "1635480", "15075720", "119957760", "705729024", "6324040800", "130989549600", "3572031415680", "78736127656320", "1502102645890560", "25514633892182400", "423898384988494080", "7590291773745542400", "162254912688831916800", "4023271392778314673920" ]
[ "sign" ]
10
0
4
[ "A089064", "A368165", "A368173", "A380338", "A380339" ]
null
Seiichi Manyama, Jan 22 2025
2025-01-22T06:39:27
oeisdata/seq/A380/A380339.seq
e64c7fb000a303e0b0305ef3ff677587
A380340
a(n) = phi(1 + phi(2 + phi(3 + ... phi(n)))).
[ "1", "1", "2", "2", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4", "4" ]
[ "nonn", "easy" ]
31
1
3
[ "A000010", "A132857", "A380340", "A380341", "A380342", "A380354", "A380414", "A380415" ]
null
Michel Marcus, Jan 22 2025
2025-01-27T06:22:32
oeisdata/seq/A380/A380340.seq
3a332cdb178f5188acdc2e6e295f32fe
A380341
a(n) = phi(1 + phi(4 + phi(9 + ... phi(n^2)))).
[ "1", "2", "4", "6", "6", "6", "16", "16", "22", "16", "16", "16", "16", "22", "22", "16", "22", "16", "16", "16", "16", "16", "16", "22", "16", "22", "16", "16", "16", "22", "22", "22", "22", "22", "22", "16", "16", "22", "16", "22", "16", "16", "16", "16", "16", "16", "22", "16", "16", "16", "16", "16", "22", "16", "16", "16", "16", "16", "22", "16", "16", "16", "16", "16", "16", "16", "16", "16", "22" ]
[ "nonn", "easy" ]
28
1
2
[ "A000010", "A380340", "A380341", "A380342", "A380354", "A380414", "A380415" ]
null
Michel Marcus, Jan 22 2025
2025-01-27T06:22:35
oeisdata/seq/A380/A380341.seq
b0ba40216d58b1bc3d1031f3f91109ea
A380342
a(n) = phi(1 + phi(8 + phi(27 + ... phi(n^3)))).
[ "1", "4", "12", "12", "36", "40", "36", "72", "156", "112", "48", "112", "110", "116", "72", "72", "36", "88", "72", "88", "116", "88", "88", "36", "48", "72", "88", "96", "88", "88", "88", "116", "116", "72", "36", "88", "116", "116", "36", "88", "116", "112", "48", "72", "112", "116", "116", "116", "116", "116", "88", "88", "72", "88", "116", "116", "88", "72", "88", "88", "88", "36", "116" ]
[ "nonn" ]
29
1
2
[ "A000010", "A380340", "A380341", "A380342", "A380354", "A380414", "A380415" ]
null
Michel Marcus, Jan 22 2025
2025-01-27T06:22:39
oeisdata/seq/A380/A380342.seq
919e070715361e82edfd964a9af1cb4d
A380343
Number of strict integer partitions of n whose product of parts is a multiple of n + 1.
[ "1", "0", "0", "0", "0", "1", "0", "1", "0", "1", "0", "3", "0", "3", "5", "5", "0", "8", "0", "15", "11", "8", "0", "42", "8", "12", "26", "49", "0", "100", "0", "90", "56", "27", "105", "246", "0", "41", "108", "414", "0", "450", "0", "332", "651", "81", "0", "1341", "210", "693", "366", "754", "0", "1869", "1044", "2579", "634", "206", "0", "5695", "0", "278", "4850", "5927", "2802" ]
[ "nonn" ]
7
0
12
[ "A000009", "A000041", "A001055", "A003963", "A025147", "A057567", "A057568", "A069016", "A096276", "A111133", "A114324", "A301987", "A318029", "A319000", "A319005", "A319916", "A325037", "A325038", "A325042", "A325044", "A326149", "A326152", "A326155", "A326156", "A379319", "A379320", "A379666", "A379671", "A379720", "A379721", "A379722", "A379733", "A379734", "A379736", "A380216", "A380217", "A380218", "A380219", "A380343" ]
null
Gus Wiseman, Jan 22 2025
2025-01-23T00:19:02
oeisdata/seq/A380/A380343.seq
acc78e41efb6506b71b633244f21afa2
A380344
Product of prime indices minus sum of prime factors of n.
[ "1", "-1", "-1", "-3", "-2", "-3", "-3", "-5", "-2", "-4", "-6", "-5", "-7", "-5", "-2", "-7", "-10", "-4", "-11", "-6", "-2", "-8", "-14", "-7", "-1", "-9", "-1", "-7", "-19", "-4", "-20", "-9", "-4", "-12", "0", "-6", "-25", "-13", "-4", "-8", "-28", "-4", "-29", "-10", "1", "-16", "-32", "-9", "2", "-3", "-6", "-11", "-37", "-3", "-1", "-9", "-6", "-21", "-42", "-6", "-43" ]
[ "sign" ]
9
1
4
[ "A000027", "A000040", "A000720", "A001222", "A001223", "A001414", "A003963", "A027746", "A055396", "A056239", "A061395", "A075254", "A075255", "A112798", "A175508", "A178503", "A319000", "A325032", "A325033", "A325034", "A325035", "A325036", "A325040", "A331384", "A379681", "A379682", "A380220", "A380344", "A380345", "A380409", "A380410" ]
null
Gus Wiseman, Jan 24 2025
2025-01-26T09:12:56
oeisdata/seq/A380/A380344.seq
b95d45c80dd36d755c182fd94b75de9a
A380345
a(n) = n + sum of prime indices of n.
[ "1", "3", "5", "6", "8", "9", "11", "11", "13", "14", "16", "16", "19", "19", "20", "20", "24", "23", "27", "25", "27", "28", "32", "29", "31", "33", "33", "34", "39", "36", "42", "37", "40", "42", "42", "42", "49", "47", "47", "46", "54", "49", "57", "51", "52", "56", "62", "54", "57", "57", "60", "60", "69", "61", "63", "63", "67", "69", "76", "67", "79", "74", "71", "70", "74", "74", "86" ]
[ "nonn" ]
5
1
2
[ "A000027", "A000040", "A000720", "A001222", "A001223", "A001414", "A003963", "A027746", "A055396", "A056239", "A061395", "A075254", "A075255", "A112798", "A175508", "A178503", "A319000", "A325032", "A325033", "A325034", "A325035", "A325036", "A325040", "A331384", "A379681", "A379682", "A380220", "A380344", "A380345", "A380409" ]
null
Gus Wiseman, Jan 25 2025
2025-01-26T09:13:00
oeisdata/seq/A380/A380345.seq
60701c7793e8d65d42be44f5cf1b9cf4
A380346
Number of corona for a hexagon of edge n with diamonds of side 1.
[ "18", "198", "1298", "5778", "19602", "54758", "132498", "287298", "571538", "1060902" ]
[ "nonn", "more" ]
38
0
1
[ "A001014", "A008793", "A016766", "A016945", "A380346", "A380416" ]
null
Craig Knecht, Jan 22 2025
2025-05-05T11:44:39
oeisdata/seq/A380/A380346.seq
74a1263f217f1935562beea134e44167
A380347
a(1) = 1, a(2) = 3; thereafter, a(n) is the smallest nonnegative integer not yet in the sequence such that both a(n-2) + a(n-1) + a(n) and their concatenation are primes.
[ "1", "3", "7", "9", "27", "17", "23", "13", "31", "53", "73", "47", "29", "21", "33", "19", "37", "41", "11", "57", "63", "77", "51", "101", "59", "67", "151", "93", "109", "49", "39", "79", "81", "91", "181", "107", "161", "43", "163", "71", "83", "87", "69", "113", "89", "61", "131", "157", "233", "133", "137", "139", "203", "179", "117", "143", "171", "207", "241", "121", "159" ]
[ "nonn", "base", "easy" ]
22
1
2
[ "A000040", "A380347" ]
null
Paolo P. Lava, Jan 22 2025
2025-01-26T14:42:13
oeisdata/seq/A380/A380347.seq
2413857160418be4d11f853b57c0eb3c
A380348
Tetraprimes (or products of exactly four distinct prime numbers) that are the sum of two successive tetraprimes.
[ "4785", "11739", "13035", "14685", "17535", "17690", "24115", "24871", "26061", "28203", "33605", "34419", "35061", "37515", "37765", "37851", "38335", "40803", "41205", "48202", "48685", "48895", "49215", "52535", "52955", "55605", "58179", "58245", "59015", "59345", "59595", "62643", "62895", "64785", "66815", "70091", "71205", "71355", "72215" ]
[ "nonn" ]
12
1
1
[ "A001043", "A046386", "A092192", "A380316", "A380348" ]
null
Massimo Kofler, Jan 22 2025
2025-02-07T00:47:46
oeisdata/seq/A380/A380348.seq
122ea169555384ec56340bf98c131f0e
A380349
In the ternary expansion of n, from left to right: replace the first, third, fifth, etc. nonzero digit, says d, by 3-d.
[ "0", "2", "1", "6", "7", "8", "3", "4", "5", "18", "19", "20", "21", "23", "22", "24", "26", "25", "9", "10", "11", "12", "14", "13", "15", "17", "16", "54", "55", "56", "57", "59", "58", "60", "62", "61", "63", "65", "64", "69", "70", "71", "66", "67", "68", "72", "74", "73", "78", "79", "80", "75", "76", "77", "27", "28", "29", "30", "32", "31", "33", "35", "34", "36", "38", "37", "42", "43" ]
[ "nonn", "base", "easy" ]
9
0
2
[ "A004488", "A380349", "A380350", "A380351", "A380352" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-24T08:47:36
oeisdata/seq/A380/A380349.seq
a6b7169ec6ee78b97ccc295028e4fd23
A380350
In the ternary expansion of n, from left to right: replace the second, fourth, sixth, etc. nonzero digit, says d, by 3-d.
[ "0", "1", "2", "3", "5", "4", "6", "8", "7", "9", "11", "10", "15", "16", "17", "12", "13", "14", "18", "20", "19", "24", "25", "26", "21", "22", "23", "27", "29", "28", "33", "34", "35", "30", "31", "32", "45", "46", "47", "48", "50", "49", "51", "53", "52", "36", "37", "38", "39", "41", "40", "42", "44", "43", "54", "56", "55", "60", "61", "62", "57", "58", "59", "72", "73", "74", "75", "77" ]
[ "nonn", "base", "easy" ]
9
0
3
[ "A004488", "A038754", "A380349", "A380350", "A380351", "A380352" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-24T08:47:32
oeisdata/seq/A380/A380350.seq
69ab4b6cc606d05ddd90a04edc58440e
A380351
In the ternary expansion of n, from right to left: replace the first, third, fifth, etc. nonzero digit, says d, by 3-d.
[ "0", "2", "1", "6", "5", "4", "3", "8", "7", "18", "11", "10", "15", "23", "22", "12", "26", "25", "9", "20", "19", "24", "14", "13", "21", "17", "16", "54", "29", "28", "33", "59", "58", "30", "62", "61", "45", "65", "64", "69", "50", "49", "66", "53", "52", "36", "74", "73", "78", "41", "40", "75", "44", "43", "27", "56", "55", "60", "32", "31", "57", "35", "34", "72", "38", "37", "42", "77" ]
[ "nonn", "base", "easy" ]
8
0
2
[ "A004488", "A380349", "A380350", "A380351", "A380352" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-24T08:47:27
oeisdata/seq/A380/A380351.seq
e873ccd61d7957c0671a1e88df1e9b21
A380352
In the ternary expansion of n, from right to left: replace the second, fourth, sixth, etc. nonzero digit, says d, by 3-d.
[ "0", "1", "2", "3", "7", "8", "6", "4", "5", "9", "19", "20", "21", "16", "17", "24", "13", "14", "18", "10", "11", "12", "25", "26", "15", "22", "23", "27", "55", "56", "57", "34", "35", "60", "31", "32", "63", "46", "47", "48", "70", "71", "51", "67", "68", "72", "37", "38", "39", "79", "80", "42", "76", "77", "54", "28", "29", "30", "61", "62", "33", "58", "59", "36", "73", "74", "75", "43" ]
[ "nonn", "base", "easy" ]
8
0
3
[ "A004488", "A038754", "A380349", "A380350", "A380351", "A380352" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-24T08:48:53
oeisdata/seq/A380/A380352.seq
06b3967bf7ebfe6ddc5dd0e1c7592dbb
A380353
a(n) = (n^2 - n + 2) * (5*n^2 - 5*n + 2) / 4.
[ "1", "12", "64", "217", "561", "1216", "2332", "4089", "6697", "10396", "15456", "22177", "30889", "41952", "55756", "72721", "93297", "117964", "147232", "181641", "221761", "268192", "321564", "382537", "451801", "530076", "618112", "716689", "826617", "948736", "1083916", "1233057", "1397089", "1576972", "1773696", "1988281", "2221777" ]
[ "nonn", "easy" ]
26
1
2
[ "A000124", "A005448", "A051624", "A072474", "A380353" ]
null
Kelvin Voskuijl, Jan 22 2025
2025-02-09T18:09:57
oeisdata/seq/A380/A380353.seq
f612017eb02e20c252c0614f5a90b7aa
A380354
a(n) = phi(2 + phi(3 + phi(5 + ... + phi(prime(n))))), where phi is Euler totient function (A000010).
[ "1", "2", "4", "6", "4", "8", "8", "12", "12", "16", "20", "20", "18", "40", "40", "16", "18", "18", "16", "72", "40", "16", "40", "18", "96", "96", "18", "64", "20", "40", "20", "48", "42", "40", "42", "20", "20", "40", "40", "20", "18", "20", "64", "64", "20", "40", "40", "40", "40", "20", "40", "20", "18", "64", "64", "40", "40", "20", "40", "20", "40", "64", "20", "40", "40", "20", "20", "64", "64", "64" ]
[ "nonn" ]
20
1
2
[ "A000010", "A380340", "A380341", "A380342", "A380354", "A380414", "A380415" ]
null
Paolo Xausa, Jan 22 2025
2025-01-27T06:51:53
oeisdata/seq/A380/A380354.seq
8119006f71704572f08fa20a743042f0
A380355
Numbers k such that (47^k - 2^k)/45 is prime.
[ "17", "103", "773", "2467", "41969" ]
[ "nonn", "hard", "more" ]
9
1
1
[ "A062587", "A062589", "A127996", "A127997", "A128344", "A204940", "A217320", "A225807", "A229542", "A375161", "A375236", "A377031", "A380355" ]
null
Robert Price, Jan 22 2025
2025-02-16T08:34:07
oeisdata/seq/A380/A380355.seq
6b9585998882b3c3e4afc3a6a41a1f04
A380356
a(0) = 0, a(1) = 1, and for any n > 0, if a(n) is at square distance from the least integer (in absolute value) not yet in the sequence and of opposite sign to a(n), say u, then a(n+1) = u, otherwise a(n+1) = a(n) + sign(a(n)).
[ "0", "1", "2", "3", "-1", "-2", "-3", "-4", "-5", "4", "5", "6", "7", "8", "9", "10", "-6", "-7", "-8", "-9", "-10", "-11", "-12", "-13", "-14", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "-15", "-16", "-17", "-18", "-19", "-20", "-21", "-22", "-23", "-24", "-25", "-26", "-27", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35" ]
[ "sign", "easy" ]
8
0
3
[ "A377091", "A380356", "A380357" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-23T12:31:57
oeisdata/seq/A380/A380356.seq
def993cf8f7be1da64a5558dd117d3f7
A380357
a(0) = 0, a(1) = 1, and for any n > 0, if a(n) - sign(a(n)) is not yet in the sequence then a(n+1) = a(n) - sign(a(n)), otherwise a(n+1) is the least integer (in absolute value) of opposite sign to a(n), at square distance from a(n) and not yet in the sequence.
[ "0", "1", "-3", "-2", "-1", "3", "2", "-7", "-6", "-5", "-4", "5", "4", "-12", "-11", "-10", "-9", "-8", "8", "7", "6", "-19", "-18", "-17", "-16", "-15", "-14", "-13", "12", "11", "10", "9", "-27", "-26", "-25", "-24", "-23", "-22", "-21", "-20", "16", "15", "14", "13", "-36", "-35", "-34", "-33", "-32", "-31", "-30", "-29", "-28", "21", "20", "19", "18", "17", "-47", "-46" ]
[ "sign" ]
5
0
3
[ "A377091", "A380356", "A380357" ]
null
Rémy Sigrist, Jan 22 2025
2025-01-23T12:32:16
oeisdata/seq/A380/A380357.seq
55ea118070d9b306f360c53e4afabd86
A380358
Numbers whose binary expansion ends with 11 and does not contain adjacent zeros.
[ "3", "7", "11", "15", "23", "27", "31", "43", "47", "55", "59", "63", "87", "91", "95", "107", "111", "119", "123", "127", "171", "175", "183", "187", "191", "215", "219", "223", "235", "239", "247", "251", "255", "343", "347", "351", "363", "367", "375", "379", "383", "427", "431", "439", "443", "447", "471", "475", "479", "491", "495", "503", "507", "511", "683" ]
[ "nonn", "base" ]
26
1
1
[ "A003754", "A052499", "A247648", "A365808", "A365809", "A380358" ]
null
R. J. Cintra, Jan 22 2025
2025-02-12T18:44:37
oeisdata/seq/A380/A380358.seq
d60facea69c2e5f02fd086dc81a97201
A380359
a(n) is the number of integers in base n such that all the integers given by their first k digits are divisible by k and which cannot be extended further.
[ "1", "3", "8", "21", "54", "145", "367", "1039", "2492", "6709", "16799", "46610", "95597", "368134", "831886", "2245056", "6084180", "15798495", "41456343", "119786906", "292818176", "788255058", "2061079489", "5753392327", "14984432350" ]
[ "nonn", "base", "more" ]
41
2
2
[ "A109032", "A109783", "A271374", "A380359" ]
null
Inigo Quilez, Jan 22 2025
2025-02-18T08:59:49
oeisdata/seq/A380/A380359.seq
2cff1dadffa4ef274ae107b8fa6d19d8
A380360
Number of embeddings on the sphere of Halin graphs on n unlabeled nodes up to orientation-preserving homeomorphisms.
[ "0", "0", "0", "1", "1", "2", "2", "4", "7", "16", "32", "76", "181", "443", "1098", "2793", "7127", "18458", "48128", "126580", "334955", "892187", "2388674", "6428489", "17377599", "47174939", "128555088", "351580903", "964696719", "2655197386", "7329051870", "20284610084", "56283140111", "156537249660", "436338547904", "1218824493990", "3411297202411" ]
[ "nonn" ]
13
1
6
[ "A005043", "A295633", "A346779", "A380360", "A380361", "A380362" ]
null
Andrew Howroyd, Jan 25 2025
2025-01-26T17:42:47
oeisdata/seq/A380/A380360.seq
282b073d22b27d4fbec97974dfb9b06a
A380361
Triangle read by rows: T(n,k) is the number of embeddings on the sphere of Halin graphs on n unlabeled nodes with circuit rank k up to orientation-preserving homeomorphisms, 3 <= k <= n-1.
[ "1", "0", "1", "0", "1", "1", "0", "0", "1", "1", "0", "0", "1", "2", "1", "0", "0", "0", "4", "2", "1", "0", "0", "0", "4", "8", "3", "1", "0", "0", "0", "0", "12", "16", "3", "1", "0", "0", "0", "0", "6", "40", "25", "4", "1", "0", "0", "0", "0", "0", "43", "93", "40", "4", "1", "0", "0", "0", "0", "0", "19", "165", "197", "56", "5", "1", "0", "0", "0", "0", "0", "0", "143", "505", "364", "80", "5", "1" ]
[ "nonn", "tabl" ]
12
4
14
[ "A000012", "A001683", "A003455", "A295633", "A380360", "A380361", "A380362" ]
null
Andrew Howroyd, Jan 25 2025
2025-01-26T17:42:42
oeisdata/seq/A380/A380361.seq
2e844a2f671bc10e3e8182e307fb72ca
A380362
Triangle read by rows: T(n,k) is the number of Halin graphs on n unlabeled nodes with circuit rank k, 3 <= k <= n-1.
[ "1", "0", "1", "0", "1", "1", "0", "0", "1", "1", "0", "0", "1", "2", "1", "0", "0", "0", "3", "2", "1", "0", "0", "0", "3", "6", "3", "1", "0", "0", "0", "0", "7", "11", "3", "1", "0", "0", "0", "0", "4", "24", "17", "4", "1", "0", "0", "0", "0", "0", "24", "51", "26", "4", "1", "0", "0", "0", "0", "0", "12", "89", "109", "36", "5", "1", "0", "0", "0", "0", "0", "0", "74", "265", "194", "50", "5", "1", "0", "0", "0", "0", "0", "0", "27", "371", "660", "345", "65", "6", "1" ]
[ "nonn", "tabl" ]
10
4
14
[ "A000012", "A000207", "A001004", "A295634", "A346779", "A380361", "A380362" ]
null
Andrew Howroyd, Jan 25 2025
2025-01-26T17:42:37
oeisdata/seq/A380/A380362.seq
41514d6194c54ed2553a72cf383eacd7
A380363
Triangle read by rows: T(n,k) is the number of linear trees with n vertices and k vertices of degree >= 3, 0 <= k <= max(0, floor(n/2)-1).
[ "1", "1", "1", "1", "1", "1", "1", "2", "1", "4", "1", "1", "7", "3", "1", "11", "10", "1", "1", "17", "24", "5", "1", "25", "56", "22", "1", "1", "36", "114", "74", "6", "1", "50", "224", "219", "37", "1", "1", "70", "411", "576", "158", "8", "1", "94", "733", "1394", "591", "58", "1", "1", "127", "1252", "3150", "1896", "304", "9", "1", "168", "2091", "6733", "5537", "1342", "82", "1" ]
[ "nonn", "tabf" ]
13
0
8
[ "A000012", "A004250", "A130131", "A238415", "A338706", "A338707", "A338708", "A380363" ]
null
Andrew Howroyd, Jan 26 2025
2025-01-26T20:27:22
oeisdata/seq/A380/A380363.seq
97217e3c2926e103fd3a23b41aec6b50
A380364
Number of rooted combinatorial maps with n edges and without faces of degree 1.
[ "1", "1", "4", "30", "284", "3240", "43282", "662760", "11446844", "220193310", "4669558564", "108251161920", "2723857695362", "73941952968000", "2154117314613604", "67038931862069790", "2219781607638887804", "77922680046440538600", "2890682855602209593362", "112998995448368143038120", "4642614436461699746566364" ]
[ "nonn" ]
6
0
3
[ "A000166", "A123023", "A379433", "A380364", "A380365", "A380366" ]
null
Andrew Howroyd, Jan 28 2025
2025-01-28T15:28:56
oeisdata/seq/A380/A380364.seq
17d0f0d5545917636b55a966eaf0b3cd
A380365
Number of sensed combinatorial maps with n edges and without faces of degree 1.
[ "1", "1", "3", "11", "50", "365", "3782", "47935", "718202", "12245679", "233541489", "4920828395", "113495838798", "2843930973805", "76932818058660", "2234631397864123", "69368177318863458", "2291843543825994905", "80296746074069588380", "2973657775519950500203", "116065360915389313936460" ]
[ "nonn" ]
7
0
3
[ "A006388", "A170946", "A380364", "A380365", "A380366" ]
null
Andrew Howroyd, Jan 28 2025
2025-01-28T15:28:52
oeisdata/seq/A380/A380365.seq
625f453f31eb8594e39b68371a5fc5e1
A380366
Number of unsensed combinatorial maps with n edges and without faces of degree 1.
[ "1", "1", "3", "11", "48", "291", "2464", "27146", "377966", "6239425" ]
[ "nonn", "more" ]
4
0
3
[ "A006389", "A214816", "A380364", "A380365", "A380366" ]
null
Andrew Howroyd, Jan 28 2025
2025-01-28T15:28:48
oeisdata/seq/A380/A380366.seq
9b7bd10a10f65a385efcac98f941b6cc
A380367
Array read by antidiagonals: meandric numbers for a river crossing up to k parallel roads at n points, n >= 0, k >= 1.
[ "1", "1", "1", "1", "1", "1", "1", "1", "2", "2", "1", "1", "2", "3", "3", "1", "1", "2", "4", "8", "8", "1", "1", "2", "4", "9", "14", "14", "1", "1", "2", "4", "10", "21", "43", "42", "1", "1", "2", "4", "10", "22", "52", "81", "81", "1", "1", "2", "4", "10", "23", "61", "131", "272", "262", "1", "1", "2", "4", "10", "23", "62", "142", "345", "538", "538", "1", "1", "2", "4", "10", "23", "63", "153", "420", "915", "1920", "1828" ]
[ "nonn", "tabl" ]
8
0
9
[ "A005316", "A076875", "A076876", "A204352", "A206432", "A208062", "A208126", "A208452", "A208453", "A209383", "A209621", "A209622", "A209626", "A209656", "A209657", "A209660", "A209707", "A210344", "A210478", "A210567", "A210592", "A380367" ]
null
Andrew Howroyd, Jan 31 2025
2025-01-31T17:22:07
oeisdata/seq/A380/A380367.seq
b825c69c654842e16fe063edebb6bf19
A380368
Triangle read by rows: T(n,k) is the number of closed forest meander systems with 2n crossings and k components.
[ "1", "0", "1", "0", "2", "1", "0", "8", "6", "1", "0", "42", "42", "12", "1", "0", "262", "320", "130", "20", "1", "0", "1828", "2618", "1360", "310", "30", "1", "0", "13820", "22582", "14196", "4270", "630", "42", "1", "0", "110954", "203006", "149024", "55524", "11060", "1148", "56", "1", "0", "933458", "1886004", "1577712", "698952", "175560", "25032", "1932", "72", "1" ]
[ "nonn", "tabl" ]
22
0
5
[ "A000012", "A002378", "A005315", "A006657", "A008828", "A060148", "A060174", "A060198", "A380368" ]
null
Andrew Howroyd, Jan 31 2025
2025-02-03T14:04:19
oeisdata/seq/A380/A380368.seq
a6aa35fb347ec4876a9352f3df83c4f6
A380369
Triangle read by rows: T(n,k) is the number of open meanders with 2n crossings and k exterior top arches, 0 <= k <= n.
[ "1", "0", "1", "0", "2", "1", "0", "7", "6", "1", "0", "36", "32", "12", "1", "0", "221", "202", "94", "20", "1", "0", "1530", "1417", "728", "220", "30", "1", "0", "11510", "10752", "5854", "2090", "445", "42", "1", "0", "92114", "86554", "48942", "19300", "5160", "812", "56", "1", "0", "773259", "729716", "423778", "178478", "54758", "11396", "1372", "72", "1", "0", "6743122", "6384353", "3781926", "1669062", "561514", "138866", "23072", "2184", "90", "1" ]
[ "nonn", "tabl" ]
14
0
5
[ "A000012", "A002378", "A005316", "A006660", "A077054", "A077056", "A259689", "A259974", "A380369" ]
null
Andrew Howroyd, Feb 01 2025
2025-02-01T19:58:11
oeisdata/seq/A380/A380369.seq
b6d1788dc34a1cc9d54ae879a0f9dd81
A380370
Expansion of e.g.f. log( 1 - log(1 - x)^5 / 120 ).
[ "0", "0", "0", "0", "0", "1", "15", "175", "1960", "22449", "269199", "3410000", "45753180", "650179816", "9771920158", "155020511282", "2589903552600", "45462951235584", "836599468436514", "16102788580144350", "323508284210923974", "6770014833358706076", "147290030512050486060", "3325319844639779998836" ]
[ "nonn" ]
11
0
7
[ "A346966", "A377376", "A379674", "A380370" ]
null
Seiichi Manyama, Jan 23 2025
2025-01-23T08:31:36
oeisdata/seq/A380/A380370.seq
e4a6d66135be36b7c5298588afbe73ac
A380371
a(n) is the integer part of the area of a rhombus with side n and angle n degrees.
[ "0", "0", "0", "0", "1", "2", "3", "5", "8", "12", "17", "23", "29", "38", "47", "58", "70", "84", "100", "117", "136", "158", "181", "206", "234", "264", "296", "330", "368", "407", "450", "494", "542", "593", "646", "702", "761", "823", "889", "957", "1028", "1102", "1180", "1261", "1344", "1431", "1522", "1615", "1712", "1812", "1915", "2021", "2130", "2243", "2359" ]
[ "nonn", "easy", "fini", "full" ]
32
0
6
null
null
Nicolay Avilov, Jan 23 2025
2025-01-31T04:28:19
oeisdata/seq/A380/A380371.seq
faed5558f13de212fce974ff1d48ffed
A380372
Characteristic function of A082851.
[ "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "0", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "0", "0", "0", "1", "0", "0", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "0", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "1", "1", "0", "1", "1", "1", "0", "1", "0", "0", "1", "0", "0", "0" ]
[ "nonn" ]
43
1
null
[ "A082850", "A082851", "A380372" ]
null
Jwalin Bhatt, Jan 23 2025
2025-02-10T11:13:11
oeisdata/seq/A380/A380372.seq
aece4e9235efc9b57e853211708225d1
A380373
Decimal expansion of Sum_{i>=1} 1/2^A082851(i).
[ "8", "6", "4", "1", "9", "1", "3", "2", "1", "4", "9", "5", "0", "4", "5", "8", "6", "2", "8", "7", "8", "4", "6", "5", "4", "8", "0", "5", "8", "7", "7", "0", "4", "8", "0", "2", "0", "2", "3", "8", "5", "1", "8", "9", "1", "9", "2", "8", "6", "1", "4", "3", "2", "0", "5", "0", "6", "7", "0", "2", "4", "2", "4", "3", "6", "4", "3", "9", "1", "7", "8", "8", "7", "0", "8", "5", "9", "3", "2", "7", "2", "0", "2", "5", "8", "0", "9", "0", "9", "6", "3", "9", "2", "7", "6", "2", "1", "0", "2", "3", "2", "0", "9", "0", "8", "3", "1", "5" ]
[ "nonn", "cons" ]
37
0
1
[ "A082850", "A082851", "A380372", "A380373" ]
null
Jwalin Bhatt, Jan 23 2025
2025-02-09T14:32:41
oeisdata/seq/A380/A380373.seq
ba0e22e4d3b5b467bbc7186d18ad418a
A380374
Number of ways to topologically sort the strong components of a labeled digraph on [n].
[ "1", "1", "5", "90", "5542", "1252120", "1152382456", "4491243320144", "72454914124818352", "4729326805677997351296", "1238455260161143286333919616", "1298230864749797963009864293455616", "5444709289384095954326434486307506566400", "91344784292457849099764110418297773249212062720" ]
[ "nonn" ]
15
0
3
[ "A003024", "A003030", "A011266", "A053763", "A380374" ]
null
Geoffrey Critzer, Jan 23 2025
2025-01-26T15:04:55
oeisdata/seq/A380/A380374.seq
e627b915741bbc830663559c532d97f1
A380375
Delete all 0's from n, then replace each remaining digit k of n by A000005(k).
[ "1", "2", "2", "3", "2", "4", "2", "4", "3", "1", "11", "12", "12", "13", "12", "14", "12", "14", "13", "2", "21", "22", "22", "23", "22", "24", "22", "24", "23", "2", "21", "22", "22", "23", "22", "24", "22", "24", "23", "3", "31", "32", "32", "33", "32", "34", "32", "34", "33", "2", "21", "22", "22", "23", "22", "24", "22", "24", "23", "4", "41", "42", "42", "43", "42", "44", "42", "44", "43", "2", "21", "22", "22", "23", "22", "24", "22", "24", "23" ]
[ "nonn", "base" ]
16
1
2
[ "A000005", "A004719", "A380375" ]
null
Ctibor O. Zizka, Jan 23 2025
2025-02-28T08:38:44
oeisdata/seq/A380/A380375.seq
e635374cea3df6b7549ad62831c4a0cb
A380376
Numbers k such that A341721(k)/k (proportion of supporters needed to win an election when there are k voters) sets a new minimum.
[ "1", "3", "5", "7", "9", "15", "21", "25", "35", "45", "49", "63", "77", "81", "91", "99", "117", "121", "135", "143", "165", "169", "187", "195", "209", "221", "225", "247", "255", "273", "285", "289", "315", "323", "345", "357", "361", "391", "399", "425", "437", "441", "475", "483", "513", "525", "529", "567", "575", "609", "621", "625", "651", "667", "675", "713" ]
[ "nonn" ]
6
1
2
[ "A341721", "A380376", "A380380" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:01:22
oeisdata/seq/A380/A380376.seq
009b3325e194a121f7c45bb977851c24
A380377
Minimum number of total votes needed for one party to win if there are n voters divided into balanced districts, i.e., the numbers of voters in two districts may differ by at most 1.
[ "1", "2", "2", "2", "3", "3", "3", "4", "4", "4", "5", "5", "5", "6", "6", "6", "6", "7", "7", "8", "8", "8", "8", "8", "9", "9", "9", "10", "10", "10", "10", "11", "12", "12", "12", "12", "12", "12", "13", "14", "14", "14", "14", "14", "14", "15", "15", "15", "15", "16", "16", "16", "17", "18", "18", "18", "18", "18", "18", "18", "19", "20", "20", "20", "20", "20", "20", "21", "21", "21", "21", "22" ]
[ "nonn" ]
7
1
2
[ "A341721", "A380377", "A380378", "A380379", "A380380", "A380381", "A380382", "A380383" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:01:38
oeisdata/seq/A380/A380377.seq
fb3049b118ffceb790ff86a1de5aeb5d
A380378
Triangle read by rows: T(n,k) is the minimum number of total votes needed for one party to win if there are n voters divided into k balanced districts, 1 <= k <= n.
[ "1", "2", "2", "2", "2", "2", "3", "3", "2", "3", "3", "3", "3", "3", "3", "4", "4", "4", "3", "3", "4", "4", "4", "4", "4", "3", "4", "4", "5", "5", "4", "5", "4", "4", "4", "5", "5", "5", "4", "5", "5", "4", "4", "5", "5", "6", "6", "4", "5", "6", "5", "4", "5", "5", "6", "6", "6", "5", "5", "6", "6", "5", "5", "5", "6", "6", "7", "7", "6", "6", "6", "7", "6", "5", "5", "6", "6", "7", "7", "7", "6", "6", "6", "7", "7", "6", "5", "6", "6", "7", "7" ]
[ "nonn", "tabl" ]
11
1
2
[ "A380377", "A380378", "A380379", "A380380", "A380381", "A380382", "A380383" ]
null
Pontus von Brömssen, Jan 24 2025
2025-06-11T09:30:07
oeisdata/seq/A380/A380378.seq
8353726cd9b7260d7f844902be14dcb0
A380379
Least k for which A380377(k) = n, i.e., the least number of voters for which n supporters are needed to win an election with rules as in A380377.
[ "1", "2", "5", "8", "11", "14", "18", "20", "25", "28", "32", "33", "39", "40", "46", "50", "53", "54", "61", "62", "68", "72", "74", "75", "83", "86", "88", "94", "98", "99", "105", "106", "113", "116", "117", "124", "128", "129", "130", "138", "143", "144", "150", "151", "158", "162", "163", "164", "173", "176", "181", "182", "188", "189", "196", "200", "203", "204", "205" ]
[ "nonn" ]
6
1
2
[ "A380377", "A380379", "A380380" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:02:02
oeisdata/seq/A380/A380379.seq
9df38dd228c6ac3bcfc7c1fde84a5e6d
A380380
Numbers k such that A380377(k)/k (proportion of supporters needed to win an election when there are k voters) sets a new minimum.
[ "1", "3", "4", "7", "10", "13", "16", "17", "23", "24", "31", "38", "45", "49", "59", "60", "67", "71", "82", "93", "97", "104", "111", "112", "123", "127", "142", "157", "161", "172", "180", "195", "199", "218", "229", "237", "241", "256", "264", "283", "287", "310", "325", "333", "337", "356", "364", "379", "387", "391", "418", "437", "445", "449", "472", "480", "499" ]
[ "nonn" ]
6
1
2
[ "A380376", "A380377", "A380379", "A380380" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:02:12
oeisdata/seq/A380/A380380.seq
b1ec5ad3c8c64596954cb112f3a0faa1
A380381
Smallest number of districts needed for A380377(n).
[ "1", "1", "1", "3", "1", "4", "5", "3", "3", "3", "3", "8", "9", "3", "3", "3", "5", "5", "13", "3", "3", "3", "7", "7", "5", "5", "5", "3", "9", "9", "9", "9", "3", "3", "5", "5", "5", "7", "7", "3", "12", "12", "13", "13", "13", "5", "5", "9", "9", "7", "7", "7", "7", "5", "5", "5", "5", "11", "11", "11", "11", "7", "7", "7", "7", "7", "9", "9", "13", "13", "13", "13", "21", "21", "5", "5", "5", "7", "7", "7", "11" ]
[ "nonn" ]
6
1
4
[ "A380377", "A380378", "A380381", "A380382" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:02:24
oeisdata/seq/A380/A380381.seq
59fdb9bb56b4f9812eb9ac3759428539
A380382
Largest number of districts possible for A380377(n).
[ "1", "2", "3", "3", "5", "5", "5", "7", "7", "7", "9", "9", "9", "11", "11", "11", "5", "13", "13", "15", "15", "15", "7", "7", "17", "5", "5", "19", "9", "9", "9", "9", "23", "23", "11", "11", "11", "11", "11", "27", "13", "13", "13", "13", "13", "13", "9", "9", "9", "15", "15", "15", "15", "17", "17", "17", "17", "17", "17", "11", "11", "19", "19", "19", "19", "19", "9", "13", "13", "13", "13", "21" ]
[ "nonn" ]
7
1
2
[ "A380377", "A380378", "A380381", "A380382" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:02:33
oeisdata/seq/A380/A380382.seq
76c8d38c69ae8c865551edbfc3255b48
A380383
Numbers k such that the minimum number of votes A380377(k) can be attained with an even number of districts.
[ "2", "3", "5", "6", "8", "9", "11", "12", "14", "15", "18", "20", "21", "28", "33", "34", "35", "40", "41", "42", "54", "55", "56", "62", "63", "75", "76", "77", "88", "99", "130", "131", "132", "164", "165", "206", "207", "208", "209", "210", "300", "341", "342" ]
[ "nonn", "more" ]
6
1
1
[ "A380377", "A380378", "A380383" ]
null
Pontus von Brömssen, Jan 24 2025
2025-01-26T21:02:48
oeisdata/seq/A380/A380383.seq
1871a9e2683b29b76ec08b49fce02dc7
A380384
a(0)=0, a(n) = 2*(a(n-1) + ceiling(n/2)) - 1 for n>0.
[ "0", "1", "3", "9", "21", "47", "99", "205", "417", "843", "1695", "3401", "6813", "13639", "27291", "54597", "109209", "218435", "436887", "873793", "1747605", "3495231", "6990483", "13980989", "27962001", "55924027", "111848079", "223696185", "447392397", "894784823", "1789569675", "3579139381", "7158278793", "14316557619" ]
[ "nonn", "easy" ]
23
0
3
[ "A081254", "A109613", "A250777", "A380384" ]
null
Paul Curtz, Jan 23 2025
2025-02-05T22:25:42
oeisdata/seq/A380/A380384.seq
f6a53488b0bcebdbd8910bcc8065d255
A380385
Triangle read by rows. T(1, 1) = 1, T(n, k) = [n >= k](Sum_{i=1..k-1} T[n - i, k - 1] - Sum_{i=1..n-1} T[n - i, k]).
[ "1", "0", "1", "0", "-1", "1", "0", "0", "-1", "1", "0", "0", "-1", "-1", "1", "0", "0", "1", "-1", "-1", "1", "0", "0", "0", "0", "-1", "-1", "1", "0", "0", "0", "1", "0", "-1", "-1", "1", "0", "0", "0", "1", "0", "0", "-1", "-1", "1", "0", "0", "0", "-1", "2", "0", "0", "-1", "-1", "1", "0", "0", "0", "0", "0", "1", "0", "0", "-1", "-1", "1", "0", "0", "0", "0", "0", "1", "1", "0", "0", "-1", "-1", "1" ]
[ "sign", "tabl" ]
20
1
50
[ "A008284", "A010815", "A231599", "A380385" ]
null
Mats Granvik, Jan 23 2025
2025-01-25T13:54:07
oeisdata/seq/A380/A380385.seq
6d2c8ab6f08de1d8e8f022ecd3aa4d9a
A380386
a(n) is the least number k that contains, in base n, every digit once, and such that k/(n-1) (if n is even) or 2*k/(n-1) (if n is odd) is prime.
[ "2", "11", "141", "694", "8345", "123771", "2177959", "44317204", "1023456879", "26432596495", "754777787027", "23609224086522", "802772380556887", "29480883458974619", "1162849439785479135", "49030176097150555976", "2200618769387072998751", "104753196945250864149393", "5271200265927977839335179", "279576400352585478815096210" ]
[ "nonn", "base" ]
14
2
1
null
null
Robert Israel, Jan 23 2025
2025-01-23T21:50:58
oeisdata/seq/A380/A380386.seq
0575aabf5912302e78b9fcd1b34b22c7
A380387
Decimal expansion of Sum_{n>=1} lambda(n)/2^n where lambda is the Liouville function (A008836).
[ "1", "6", "2", "3", "2", "4", "6", "3", "7", "6", "2", "3", "9", "2", "9", "7", "8", "5", "9", "5", "9", "7", "9", "7", "3", "3", "5", "8", "3", "6", "2", "2", "4", "0", "9", "1", "7", "0", "0", "0", "4", "8", "3", "7", "9", "2", "2", "8", "8", "1", "5", "9", "4", "9", "1", "9", "3", "4", "4", "2", "9", "3", "8", "9", "7", "0", "7", "8", "5", "3", "2", "4", "7", "6", "9", "0", "1", "9", "5", "2", "4", "7", "9", "7", "2", "0" ]
[ "nonn", "cons" ]
10
0
2
[ "A008836", "A238270", "A300892", "A343784", "A380387" ]
null
Friedjof Tellkamp, Jan 23 2025
2025-02-15T14:16:00
oeisdata/seq/A380/A380387.seq
16e04df5acfece3f7b59b28125867971
A380388
Primes q for which A177436(pi(q)) is not equal to 2*(1 + floor(log_2(q/(2^ceiling(log_2(q))-q)))).
[ "3", "5", "11", "13", "17", "19", "43", "67", "103", "131", "241", "257", "683", "2731", "4099", "32771", "43691", "61681", "65537", "65539", "174763", "262147", "2796203", "6710887", "15790321" ]
[ "nonn", "more" ]
4
1
1
[ "A177436", "A380388" ]
null
Michel Marcus, Jan 23 2025
2025-01-23T12:39:06
oeisdata/seq/A380/A380388.seq
af69bbb70de7d21234d7a555fe0238fa
A380389
Array read by ascending antidiagonals: A(n, k) is equal to n/k if k | n, else to the concatenation of the numerator and the denominator of n/k.
[ "1", "2", "12", "3", "1", "13", "4", "32", "23", "14", "5", "2", "1", "12", "15", "6", "52", "43", "34", "25", "16", "7", "3", "53", "1", "35", "13", "17", "8", "72", "2", "54", "45", "12", "27", "18", "9", "4", "73", "32", "1", "23", "37", "14", "19", "10", "92", "83", "74", "65", "56", "47", "38", "29", "110", "11", "5", "3", "2", "75", "1", "57", "12", "13", "15", "111", "12", "112", "103", "94", "85", "76", "67", "58", "49", "310", "211", "112" ]
[ "nonn", "base", "easy", "look", "tabl" ]
10
1
2
[ "A000012", "A000027", "A003988", "A372523", "A380389", "A380390" ]
null
Stefano Spezia, Jan 23 2025
2025-01-23T21:58:27
oeisdata/seq/A380/A380389.seq
c7f1012fbac693dfdf1eb1c1f62572e6
A380390
Array read by ascending antidiagonals: A(n, k) is equal to n/k if k | n, else to the concatenation of A003988(n, k) = floor(n/k) and A380389(n - k*floor(n/k), k).
[ "1", "2", "12", "3", "1", "13", "4", "112", "23", "14", "5", "2", "1", "12", "15", "6", "212", "113", "34", "25", "16", "7", "3", "123", "1", "35", "13", "17", "8", "312", "2", "114", "45", "12", "27", "18", "9", "4", "213", "112", "1", "23", "37", "14", "19", "10", "412", "223", "134", "115", "56", "47", "38", "29", "110", "11", "5", "3", "2", "125", "1", "57", "12", "13", "15", "111" ]
[ "nonn", "base", "easy", "look", "tabl" ]
12
1
2
[ "A000012", "A000027", "A003988", "A372523", "A380389", "A380390" ]
null
Stefano Spezia, Jan 23 2025
2025-01-23T21:58:34
oeisdata/seq/A380/A380390.seq
6194c553c5231dbd20162d1e8425a32f
A380391
Numbers k such that A343750(k) != k.
[ "10", "12", "14", "16", "18", "20", "28", "30", "31", "32", "34", "35", "36", "38", "40", "42", "50", "51", "52", "54", "56", "60", "62", "64", "68", "70", "71", "72", "73", "74", "75", "76", "78", "80", "84", "85", "90", "91", "92", "93", "94", "95", "96", "97", "98", "100", "101", "102", "103", "104", "105", "106", "107", "108", "109", "110", "112", "114", "115", "116", "118", "119", "120" ]
[ "nonn", "base" ]
20
1
1
[ "A000005", "A004719", "A010785", "A272215", "A343750", "A380391" ]
null
Ctibor O. Zizka, Jan 23 2025
2025-01-25T12:39:25
oeisdata/seq/A380/A380391.seq
a77adeaf7e1131dad65743f0b711cb28
A380392
Irregular triangle read by rows: T(n,k) is the number of n X n binary matrices containing k South-East paths of 1's connecting the top left and bottom right corners.
[ "1", "1", "1", "13", "2", "1", "461", "26", "13", "8", "1", "2", "1", "61708", "1454", "953", "568", "325", "112", "178", "76", "22", "46", "48", "2", "16", "4", "4", "8", "8", "0", "1", "2", "1", "32348492", "340768", "279142", "168300", "125121", "44436", "81857", "24666", "25375", "28182", "19759", "4476", "17477", "4334", "7123", "6436", "4314", "1708", "5534" ]
[ "nonn", "tabf" ]
16
0
4
[ "A000984", "A001790", "A002416", "A086266", "A101926", "A261242", "A369285", "A380392" ]
null
John Tyler Rascoe, Jan 23 2025
2025-02-22T09:56:58
oeisdata/seq/A380/A380392.seq
1a06f2174b40c53e6af4c247790bc68f
A380393
a(n) is the least k that has exactly n proper divisors d such that (-d)^k == -d (mod k).
[ "1", "2", "6", "42", "66", "105", "2805", "561", "1365", "5005", "5565", "11305", "36465", "140505", "239785", "41041", "682465", "873145", "185185", "418285", "1683969", "2113665", "5503785", "1242241", "6697405", "8549905", "31932901", "11996985", "31260405", "30534805", "47031061", "825265", "27265161", "32306365", "55336645", "21662641", "9276085", "8964865" ]
[ "nonn" ]
18
0
2
[ "A371513", "A378387", "A380393" ]
null
Robert Israel, Jan 23 2025
2025-03-31T23:09:51
oeisdata/seq/A380/A380393.seq
d6d97962c429d2dcf354412bbd2540a7
A380394
a(n) = number of possible pairs of descent sets of a permutation of 1,2,...,n and its inverse.
[ "1", "1", "2", "6", "22", "94", "426", "1938", "8724", "38724", "169438", "731390", "3119052", "13162228" ]
[ "nonn", "more" ]
17
0
3
null
null
Richard Stanley, Jan 23 2025
2025-01-28T21:54:43
oeisdata/seq/A380/A380394.seq
8af0b2e449c2d7f5993e0bae3245bf35
A380395
The number of unitary divisors of n that are cubes.
[ "1", "1", "1", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "2", "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", "2", "1", "2", "1", "1", "1", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "2", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1" ]
[ "nonn", "easy", "mult" ]
11
1
8
[ "A000578", "A002117", "A013662", "A046100", "A056624", "A061704", "A077610", "A307427", "A318672", "A366761", "A380395", "A380396", "A380397" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T09:14:35
oeisdata/seq/A380/A380395.seq
ce0d0e0cab15fbab9fdeb1ca85116f07
A380396
a(n) is the sum of the unitary divisors of n that are cubes.
[ "1", "1", "1", "1", "1", "1", "1", "9", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "9", "1", "1", "28", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "9", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "28", "1", "9", "1", "1", "1", "1", "1", "1", "1", "65", "1", "1", "1", "1", "1", "1", "1", "9", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1" ]
[ "nonn", "easy", "mult" ]
10
1
8
[ "A000578", "A046100", "A077610", "A113061", "A358347", "A366761", "A371334", "A380395", "A380396" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T08:29:33
oeisdata/seq/A380/A380396.seq
1c0072819c76dae997d8713ea2013585
A380397
The number of nonunitary divisors of n that are cubes.
[ "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "0", "0" ]
[ "nonn", "easy" ]
10
1
null
[ "A000578", "A002117", "A013662", "A048105", "A056626", "A061704", "A295884", "A380395", "A380396", "A380397" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T08:29:36
oeisdata/seq/A380/A380397.seq
433b0e2ef36bf4723932ae315d8980d9
A380398
The number of unitary divisors of n that are perfect powers (A001597).
[ "1", "1", "1", "2", "1", "1", "1", "2", "2", "1", "1", "2", "1", "1", "1", "2", "1", "2", "1", "2", "1", "1", "1", "2", "2", "1", "2", "2", "1", "1", "1", "2", "1", "1", "1", "4", "1", "1", "1", "2", "1", "1", "1", "2", "2", "1", "1", "2", "2", "2", "1", "2", "1", "2", "1", "2", "1", "1", "1", "2", "1", "1", "2", "2", "1", "1", "1", "2", "1", "1", "1", "3", "1", "1", "2", "2", "1", "1", "1", "2", "2", "1", "1", "2", "1", "1", "1" ]
[ "nonn", "easy" ]
10
1
4
[ "A001597", "A005117", "A007424", "A008683", "A061742", "A077610", "A091050", "A118914", "A278908", "A307848", "A323308", "A358260", "A365549", "A368978", "A369163", "A380398", "A380399", "A380400" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T08:29:39
oeisdata/seq/A380/A380398.seq
725e3073893dd420b025dfdb160e97c0
A380399
The number of nonunitary divisors of n that are perfect powers (A001597).
[ "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "2", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "1", "0", "0", "0", "0", "3", "0", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "2", "0", "0", "0", "0", "0", "1", "0", "1", "0", "0", "0", "0", "0", "0", "0", "4", "0", "0", "0", "0", "0", "0", "0", "2", "0", "0", "0", "0", "0", "0", "0", "2", "2", "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "0", "0", "0", "3", "0", "0", "0", "0", "0", "0", "0", "1", "0" ]
[ "nonn", "easy" ]
10
1
16
[ "A001597", "A008683", "A048105", "A072102", "A091050", "A380398", "A380399" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T08:29:52
oeisdata/seq/A380/A380399.seq
f6a6b3ad6db37771cccd083c86fe45a9
A380400
The sum of unitary divisors of n that are perfect powers (A001597).
[ "1", "1", "1", "5", "1", "1", "1", "9", "10", "1", "1", "5", "1", "1", "1", "17", "1", "10", "1", "5", "1", "1", "1", "9", "26", "1", "28", "5", "1", "1", "1", "33", "1", "1", "1", "50", "1", "1", "1", "9", "1", "1", "1", "5", "10", "1", "1", "17", "50", "26", "1", "5", "1", "28", "1", "9", "1", "1", "1", "5", "1", "1", "10", "65", "1", "1", "1", "5", "1", "1", "1", "18", "1", "1", "26", "5", "1", "1", "1", "17", "82" ]
[ "nonn", "easy" ]
12
1
4
[ "A001597", "A005117", "A077610", "A358347", "A360720", "A380398", "A380400" ]
null
Amiram Eldar, Jan 23 2025
2025-01-25T07:49:32
oeisdata/seq/A380/A380400.seq
46ee247c1e0bddae03b665fd468e4a21
A380401
Triangle read by rows: T(n,k) is the number of necklace permutations of a multiset whose multiplicities are given by the k-th partition of n in graded reflected lexicographic order.
[ "1", "1", "1", "2", "1", "1", "6", "3", "2", "1", "1", "24", "12", "6", "4", "2", "1", "1", "120", "60", "30", "16", "20", "10", "4", "5", "3", "1", "1", "720", "360", "180", "90", "120", "60", "30", "20", "30", "15", "5", "6", "3", "1", "1", "5040", "2520", "1260", "630", "318", "840", "420", "210", "140", "70", "210", "105", "54", "35", "10", "42", "21", "7", "7", "4", "1", "1", "40320", "20160", "10080", "5040", "2520", "6720", "3360", "1680", "840", "1120", "560", "188", "1680", "840", "420", "280", "140", "70", "336", "168", "84", "56", "14", "56", "28", "10", "8", "4", "1", "1" ]
[ "nonn", "tabf" ]
29
1
4
[ "A000041", "A072605", "A080576", "A212359", "A214609", "A318810", "A334434", "A380401" ]
null
Marko Riedel, Jan 23 2025
2025-01-26T14:18:00
oeisdata/seq/A380/A380401.seq
23c019a8732e8a4d885cfe04b1e814ca
A380402
Number of proper prime powers (in A246547) that do not exceed primorial A002110(n).
[ "0", "0", "1", "6", "14", "34", "75", "187", "551", "1954", "8317", "38582", "200978", "1125541", "6562122", "40444003", "266832233", "1870169623", "13424553758", "101495825622", "793832121165", "6325729776075", "52616754936494", "450157758564742", "3999323787879764", "37180986240914714", "353667558431662474" ]
[ "nonn", "hard" ]
15
0
4
[ "A036386", "A246547", "A380402" ]
null
Michael De Vlieger, Jan 23 2025
2025-02-25T14:56:08
oeisdata/seq/A380/A380402.seq
4282109dc8cdb39e978937e998fe7062
A380403
Number of integers k that are neither squarefree nor prime powers (in A126706) and that do not exceed primorial A002110(n).
[ "0", "0", "0", "5", "67", "871", "11693", "199976", "3802411", "87466676", "2536583089", "78634293907", "2909470106300", "119288281458176", "5129396144497507", "241081619059363357", "12777325812023481231", "753862222923258499554" ]
[ "nonn", "hard", "more" ]
29
0
4
[ "A002110", "A126706", "A158341", "A380402", "A380403" ]
null
Michael De Vlieger, Jan 23 2025
2025-02-25T14:54:50
oeisdata/seq/A380/A380403.seq
e6177e58a15b63174bbb43f6aee37a0e