Datasets:
christopher
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oeis

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timestamp
timestamp[us]date
1999-12-11 03:00:00
2025-04-25 01:21:50
filename
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29
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32
32
A001701
Generalized Stirling numbers.
[ "1", "6", "26", "71", "155", "295", "511", "826", "1266", "1860", "2640", "3641", "4901", "6461", "8365", "10660", "13396", "16626", "20406", "24795", "29855", "35651", "42251", "49726", "58150", "67600", "78156", "89901", "102921", "117305", "133145", "150536", "169576", "190366", "213010", "237615", "264291", "293151", "324311" ]
[ "nonn", "easy" ]
95
0
5
[ "A001701", "A005564", "A059302", "A145324" ]
[ "M4169", "N1735" ]
N. J. A. Sloane
2024-02-29T15:41:09
oeisdata/seq/A001/A001701.seq
f61df82330cf88a7a1353e4d2187c581
A001702
Generalized Stirling numbers.
[ "1", "24", "154", "580", "1665", "4025", "8624", "16884", "30810", "53130", "87450", "138424", "211939", "315315", "457520", "649400", "903924", "1236444", "1664970", "2210460", "2897125", "3752749", "4809024", "6101900", "7671950", "9564750", "11831274", "14528304", "17718855", "21472615", "25866400", "30984624" ]
[ "nonn", "easy" ]
63
0
5
[ "A001702", "A145324" ]
[ "M5148", "N2234" ]
N. J. A. Sloane
2022-09-08T08:44:29
oeisdata/seq/A001/A001702.seq
06926143dbd2e1c7ea93b99400f974e0
A001703
Decimal concatenation of n, n+1, and n+2.
[ "12", "123", "234", "345", "456", "567", "678", "789", "8910", "91011", "101112", "111213", "121314", "131415", "141516", "151617", "161718", "171819", "181920", "192021", "202122", "212223", "222324", "232425", "242526", "252627", "262728", "272829", "282930", "293031", "303132", "313233", "323334", "333435", "343536", "353637", "363738" ]
[ "nonn", "base", "easy" ]
54
0
5
[ "A000027", "A001703", "A035333", "A074991", "A127421", "A127422", "A127423", "A127424", "A279204" ]
null
mag(AT)laurel.salles.entpe.fr
2019-12-07T03:50:34
oeisdata/seq/A001/A001703.seq
619587250ea3e337157a56b09dcd3d1b
A001704
a(n) = n concatenated with n + 1.
[ "12", "23", "34", "45", "56", "67", "78", "89", "910", "1011", "1112", "1213", "1314", "1415", "1516", "1617", "1718", "1819", "1920", "2021", "2122", "2223", "2324", "2425", "2526", "2627", "2728", "2829", "2930", "3031", "3132", "3233", "3334", "3435", "3536", "3637", "3738", "3839", "3940", "4041", "4142", "4243", "4344", "4445", "4546" ]
[ "nonn", "base", "easy" ]
75
0
5
[ "A001704", "A030457", "A127421", "A215027", "A248378" ]
null
N. J. A. Sloane
2024-01-01T02:18:55
oeisdata/seq/A001/A001704.seq
88f5a3f6f99211e561cdc761ed4b2650
A001705
Generalized Stirling numbers: a(n) = n! * Sum_{k=0..n-1} (k+1)/(n-k).
[ "0", "1", "5", "26", "154", "1044", "8028", "69264", "663696", "6999840", "80627040", "1007441280", "13575738240", "196287356160", "3031488633600", "49811492505600", "867718162483200", "15974614352793600", "309920046408806400", "6320046028584960000", "135153868608460800000", "3024476051557847040000" ]
[ "nonn", "easy" ]
160
0
5
[ "A000254", "A001008", "A001705", "A001711", "A001716", "A001721", "A002104", "A002805", "A006231", "A006675", "A051524", "A051545", "A051560", "A051562", "A051564", "A066667", "A132159", "A143947" ]
[ "M3944", "N1625" ]
N. J. A. Sloane
2025-02-03T11:54:20
oeisdata/seq/A001/A001705.seq
5cd71be9d2705cb109faf5d03e39722d
A001706
Generalized Stirling numbers.
[ "1", "9", "71", "580", "5104", "48860", "509004", "5753736", "70290936", "924118272", "13020978816", "195869441664", "3134328981120", "53180752331520", "953884282141440", "18037635241029120", "358689683932346880", "7483713725055744000", "163478034254755584000", "3731670622213083648000" ]
[ "nonn" ]
48
0
5
null
[ "M4646", "N1988" ]
N. J. A. Sloane
2024-07-30T05:30:57
oeisdata/seq/A001/A001706.seq
86cd7e08870dc25342c1efda1e10fe91
A001707
Generalized Stirling numbers.
[ "1", "14", "155", "1665", "18424", "214676", "2655764", "34967140", "489896616", "7292774280", "115119818736", "1922666722704", "33896996544384", "629429693586048", "12283618766690304", "251426391808144896", "5387217520095244800", "120615281647055884800", "2817014230489985049600" ]
[ "nonn" ]
29
0
5
null
[ "M4947", "N2119" ]
N. J. A. Sloane
2023-01-01T12:36:03
oeisdata/seq/A001/A001707.seq
86f7c7d5d7c18357ef3ae081d4ce556f
A001708
Generalized Stirling numbers.
[ "1", "20", "295", "4025", "54649", "761166", "11028590", "167310220", "2664929476", "44601786944", "784146622896", "14469012689040", "279870212258064", "5667093514231200", "119958395537083104", "2650594302549806976", "61049697873641191296", "1463708634867162093312", "36482312832434713195776" ]
[ "nonn" ]
33
0
5
null
[ "M5095", "N2206" ]
N. J. A. Sloane
2022-02-04T08:16:28
oeisdata/seq/A001/A001708.seq
63dd0e2a58001964c568a1c5d11f9225
A001709
Generalized Stirling numbers.
[ "1", "27", "511", "8624", "140889", "2310945", "38759930", "671189310", "12061579816", "225525484184", "4392554369840", "89142436976320", "1884434077831824", "41471340993035856", "949385215397800224", "22587683825903611680", "557978742043520648256", "14297219701868137003200" ]
[ "nonn" ]
25
0
5
null
[ "M5195", "N2259" ]
N. J. A. Sloane
2023-01-01T12:35:59
oeisdata/seq/A001/A001709.seq
9d55d597d4910fc8c424c2cc1b8bb599
A001710
Order of alternating group A_n, or number of even permutations of n letters.
[ "1", "1", "1", "3", "12", "60", "360", "2520", "20160", "181440", "1814400", "19958400", "239500800", "3113510400", "43589145600", "653837184000", "10461394944000", "177843714048000", "3201186852864000", "60822550204416000", "1216451004088320000", "25545471085854720000", "562000363888803840000" ]
[ "nonn", "easy", "nice" ]
351
0
5
[ "A000142", "A000153", "A000255", "A001147", "A001286", "A001710", "A001720", "A002135", "A002260", "A002674", "A007623", "A007717", "A046089", "A049444", "A049459", "A085990", "A093468", "A094587", "A094638", "A138533", "A153880", "A161739", "A173333", "A213936", "A215771", "A265609", "A307429", "A319225", "A319226", "A320655" ]
[ "M2933", "N1179" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001710.seq
18ad1cd7cd080098b95df5b6c37e54da
A001711
Generalized Stirling numbers.
[ "1", "7", "47", "342", "2754", "24552", "241128", "2592720", "30334320", "383970240", "5231113920", "76349105280", "1188825724800", "19675048780800", "344937224217600", "6386713749964800", "124548748102195200", "2551797512248320000", "54804198761303040000", "1231237843834521600000" ]
[ "nonn" ]
108
0
5
[ "A000254", "A001705", "A001711", "A001716", "A001721", "A051524", "A051545", "A051560", "A051562", "A051564" ]
[ "M4429", "N1873" ]
N. J. A. Sloane
2024-04-19T08:20:18
oeisdata/seq/A001/A001711.seq
47617fd89e81ffb0296dec86600bc611
A001712
Generalized Stirling numbers.
[ "1", "12", "119", "1175", "12154", "133938", "1580508", "19978308", "270074016", "3894932448", "59760168192", "972751628160", "16752851775360", "304473528961920", "5825460745532160", "117070467915075840", "2465958106403712000", "54336917746726272000", "1250216389189281024000" ]
[ "nonn" ]
63
0
5
[ "A001711", "A001712", "A008275", "A048994", "A163931", "A163932" ]
[ "M4861", "N2077" ]
N. J. A. Sloane
2020-06-26T11:13:37
oeisdata/seq/A001/A001712.seq
dc489ef035c9733effbd943a303af8eb
A001713
Generalized Stirling numbers.
[ "1", "18", "245", "3135", "40369", "537628", "7494416", "109911300", "1698920916", "27679825272", "474957547272", "8572072384512", "162478082312064", "3229079010579072", "67177961946534528", "1460629706845766400", "33139181950164806400", "783398920650352012800", "19268391564147377318400" ]
[ "nonn" ]
63
0
5
[ "A000254", "A001706", "A001711", "A001712", "A001713", "A001719", "A048994" ]
[ "M5060", "N2190" ]
N. J. A. Sloane
2020-06-26T13:58:50
oeisdata/seq/A001/A001713.seq
00607f24e4333be6b46bec73b7e458a2
A001714
Generalized Stirling numbers.
[ "1", "25", "445", "7140", "111769", "1767087", "28699460", "483004280", "8460980836", "154594537812", "2948470152264", "58696064973000", "1219007251826064", "26390216795274288", "594982297852020288", "13955257961738192448", "340154857108405040256", "8606960634143667938688" ]
[ "nonn" ]
45
0
5
[ "A001711", "A001712", "A001713", "A001714", "A048994", "A163931", "A163932" ]
[ "M5184", "N2252" ]
N. J. A. Sloane
2021-02-02T22:00:45
oeisdata/seq/A001/A001714.seq
71854b34400dc8f8a1b506dc17d8be6f
A001715
a(n) = n!/6.
[ "1", "4", "20", "120", "840", "6720", "60480", "604800", "6652800", "79833600", "1037836800", "14529715200", "217945728000", "3487131648000", "59281238016000", "1067062284288000", "20274183401472000", "405483668029440000", "8515157028618240000", "187333454629601280000", "4308669456480829440000" ]
[ "nonn", "easy" ]
90
0
5
[ "A000142", "A001710", "A001715", "A001720", "A007759", "A034472", "A049352", "A049458", "A049460", "A094587", "A094638", "A111530", "A130128", "A138533", "A173333", "A213936", "A245334" ]
[ "M3566", "N1445" ]
N. J. A. Sloane
2023-01-15T02:42:45
oeisdata/seq/A001/A001715.seq
30741c51e0febbbbb55e4ed22dc5d51a
A001716
Generalized Stirling numbers.
[ "1", "9", "74", "638", "5944", "60216", "662640", "7893840", "101378880", "1397759040", "20606463360", "323626665600", "5395972377600", "95218662067200", "1773217155225600", "34758188233574400", "715437948072960000", "15429680577561600000", "347968129734973440000", "8190600438533990400000" ]
[ "nonn" ]
81
0
5
[ "A000254", "A001705", "A001711", "A001716", "A001721", "A051524", "A051545", "A051560", "A051562", "A051564" ]
[ "M4651", "N1990" ]
N. J. A. Sloane
2023-01-25T11:50:25
oeisdata/seq/A001/A001716.seq
8640e49f8aab38bdfb4c3f2031fa374c
A001717
Generalized Stirling numbers.
[ "1", "15", "179", "2070", "24574", "305956", "4028156", "56231712", "832391136", "13051234944", "216374987520", "3785626465920", "69751622298240", "1350747863435520", "27437426560500480", "583506719443584000", "12969079056388224000", "300749419818102528000", "7265204785551331584000" ]
[ "nonn" ]
45
0
5
null
[ "M4984", "N2143" ]
N. J. A. Sloane
2020-06-26T13:59:00
oeisdata/seq/A001/A001717.seq
c884beea7e3a84e0e03d22ee3f36fe37
A001718
Generalized Stirling numbers.
[ "1", "22", "355", "5265", "77224", "1155420", "17893196", "288843260", "4876196776", "86194186584", "1595481972864", "30908820004608", "626110382381184", "13246845128678016", "292374329134060800", "6723367631258860800", "160883166944083161600", "4001062259532015244800" ]
[ "nonn" ]
43
0
5
[ "A001716", "A001717", "A001718", "A163931", "A163934" ]
[ "M5127", "N2222" ]
N. J. A. Sloane
2020-06-27T16:23:00
oeisdata/seq/A001/A001718.seq
0154e363d237c798ecaffa1ffa5b51bf
A001719
Generalized Stirling numbers.
[ "1", "30", "625", "11515", "203889", "3602088", "64720340", "1194928020", "22800117076", "450996059800", "9262414989464", "197632289814960", "4381123888865424", "100869322905986496", "2410630110159777216", "59757230054773959552", "1535299458203884231296", "40848249256425236795904" ]
[ "nonn" ]
32
0
5
[ "A000254", "A001706", "A001713", "A001719" ]
[ "M5212", "N2266" ]
N. J. A. Sloane
2023-01-01T12:36:11
oeisdata/seq/A001/A001719.seq
f4e911d22c8e48169fa7a88b9abde911
A001720
a(n) = n!/24.
[ "1", "5", "30", "210", "1680", "15120", "151200", "1663200", "19958400", "259459200", "3632428800", "54486432000", "871782912000", "14820309504000", "266765571072000", "5068545850368000", "101370917007360000", "2128789257154560000", "46833363657400320000", "1077167364120207360000" ]
[ "nonn", "easy" ]
77
0
5
[ "A000142", "A001710", "A001715", "A001720", "A007696", "A049353", "A049459", "A051338", "A094587", "A094638", "A130534", "A138533", "A163931", "A173333", "A213936", "A245334" ]
[ "M3960", "N1634" ]
N. J. A. Sloane
2023-01-15T02:43:07
oeisdata/seq/A001/A001720.seq
69f0313d5e456654377caaa2fe4f8f9e
A001721
Generalized Stirling numbers.
[ "1", "11", "107", "1066", "11274", "127860", "1557660", "20355120", "284574960", "4243508640", "67285058400", "1131047366400", "20099588140800", "376612896038400", "7422410595801600", "153516757766400000", "3325222830101760000", "75283691519393280000", "1778358268603445760000" ]
[ "nonn" ]
42
0
5
[ "A000254", "A001705", "A001711", "A001716", "A001721", "A051524", "A051545", "A051560", "A051562", "A051564" ]
[ "M4803", "N2052" ]
N. J. A. Sloane
2021-12-24T08:17:42
oeisdata/seq/A001/A001721.seq
3f911c60d6ceb05b1ae0f6b21d24dbba
A001722
Generalized Stirling numbers.
[ "1", "18", "251", "3325", "44524", "617624", "8969148", "136954044", "2201931576", "37272482280", "663644774880", "12413008539360", "243533741849280", "5003753991174720", "107497490419296000", "2410964056571616000", "56366432074677312000", "1371711629236971456000", "34699437370290760704000" ]
[ "nonn" ]
22
0
5
null
[ "M5061", "N2191" ]
N. J. A. Sloane
2021-12-24T08:17:35
oeisdata/seq/A001/A001722.seq
56cbbf74803f605996da2375d2663108
A001723
Generalized Stirling numbers.
[ "1", "26", "485", "8175", "134449", "2231012", "37972304", "668566300", "12230426076", "232959299496", "4623952866312", "95644160132976", "2060772784375824", "46219209678691200", "1078100893671811200", "26129183717351462400", "657337657573760947200", "17147815411007234188800" ]
[ "nonn" ]
24
0
5
null
[ "M5189", "N2256" ]
N. J. A. Sloane
2021-12-24T08:17:29
oeisdata/seq/A001/A001723.seq
013b5fe8291f4553d25cd5aae65db362
A001724
Generalized Stirling numbers.
[ "1", "35", "835", "17360", "342769", "6687009", "131590430", "2642422750", "54509190076", "1159615530788", "25497032420496", "580087776122400", "13662528306823824", "333132304121991504", "8407011584355624288", "219490450157530821024", "5925108461354500651776", "165275526944869750483200" ]
[ "nonn" ]
37
0
5
null
[ "M5248", "N2282" ]
N. J. A. Sloane
2016-01-20T05:30:53
oeisdata/seq/A001/A001724.seq
5054b0df3b82489d51c39b2dcce0963c
A001725
a(n) = n!/5!.
[ "1", "6", "42", "336", "3024", "30240", "332640", "3991680", "51891840", "726485760", "10897286400", "174356582400", "2964061900800", "53353114214400", "1013709170073600", "20274183401472000", "425757851430912000", "9366672731480064000", "215433472824041472000", "5170403347776995328000" ]
[ "nonn", "easy" ]
59
0
5
[ "A000142", "A001725", "A049374", "A049460", "A051338", "A051339", "A245334" ]
[ "M4243", "N1772" ]
N. J. A. Sloane
2023-01-15T02:43:25
oeisdata/seq/A001/A001725.seq
1fe0ab7d7022e5ef77c0008ab37c885f
A001726
Weight distribution of [ 64,22,16 ] 2nd-order Reed-Muller code of length 64.
[ "1", "0", "0", "0", "2604", "0", "291648", "888832", "1828134", "888832", "291648", "0", "2604", "0", "0", "0", "1" ]
[ "nonn", "fini", "full" ]
17
0
5
null
null
N. J. A. Sloane
2023-04-12T11:25:49
oeisdata/seq/A001/A001726.seq
f689cb262ef76ab7592fdcd8c304c76d
A001727
Weight distribution of [64,42,8] 3rd-order Reed-Muller code of length 64.
[ "1", "0", "0", "0", "11160", "0", "1749888", "22855680", "232081500", "1717223424", "9366150528", "38269550592", "119637587496", "286573658112", "533982211840", "771854598144", "874731154374", "771854598144", "533982211840", "286573658112" ]
[ "nonn", "fini", "full" ]
14
0
5
[ "A001726", "A001727" ]
null
N. J. A. Sloane
2022-02-01T23:17:41
oeisdata/seq/A001/A001727.seq
3790aad223192bd9145eb4326012f79f
A001728
Expansion of cos x / cos 4x.
[ "1", "15", "1185", "230895", "83860545", "48942778575", "41893214676705", "49441928730798255", "76946148390480577665", "152682246738275154625935", "376229085883258481118811425", "1127131459348047116845576437615", "4034538627668651235506091915425985" ]
[ "nonn" ]
10
0
5
[ "A000813", "A001728" ]
null
N. J. A. Sloane
2022-02-01T01:23:58
oeisdata/seq/A001/A001728.seq
578ca9d77b8fb10869d86df98d2e8f58
A001729
List of numbers whose digits contain no loops (version 1).
[ "1", "2", "3", "4", "5", "7", "11", "12", "13", "14", "15", "17", "21", "22", "23", "24", "25", "27", "31", "32", "33", "34", "35", "37", "41", "42", "43", "44", "45", "47", "51", "52", "53", "54", "55", "57", "71", "72", "73", "74", "75", "77", "111", "112", "113", "114", "115", "117", "121", "122", "123", "124", "125", "127", "131", "132", "133", "134", "135", "137", "141", "142" ]
[ "base", "nonn", "easy" ]
23
0
5
[ "A001729", "A001742" ]
null
N. J. A. Sloane
2024-02-15T01:52:45
oeisdata/seq/A001/A001729.seq
5cd57c220d380014486021102aaf04dd
A001730
a(n) = n!/6!.
[ "1", "7", "56", "504", "5040", "55440", "665280", "8648640", "121080960", "1816214400", "29059430400", "494010316800", "8892185702400", "168951528345600", "3379030566912000", "70959641905152000", "1561112121913344000", "35905578804006912000", "861733891296165888000", "21543347282404147200000" ]
[ "nonn", "easy" ]
48
0
5
[ "A000142", "A001730", "A051338", "A051339", "A051379", "A130534", "A163931", "A173333", "A245334" ]
[ "M4436", "N1876" ]
N. J. A. Sloane
2023-01-15T02:42:09
oeisdata/seq/A001/A001730.seq
d18f8b5b6d83aa8e757718c3e122e0db
A001731
a(n) is 9 written in base 10-n.
[ "9", "10", "11", "12", "13", "14", "21", "100", "1001", "111111111" ]
[ "fini", "nonn", "base", "full" ]
16
0
5
[ "A001731", "A001732", "A001733", "A001734", "A001735", "A001736" ]
null
N. J. A. Sloane
2022-02-02T08:20:34
oeisdata/seq/A001/A001731.seq
d93ccd1dda5fcb03275c85d7a826fdf0
A001732
8 in base 10-n.
[ "8", "8", "10", "11", "12", "13", "20", "22", "1000", "11111111" ]
[ "fini", "nonn", "base", "full" ]
10
0
5
null
null
N. J. A. Sloane
2022-02-03T22:49:20
oeisdata/seq/A001/A001732.seq
ff2eee224c5a3aed9123fa307a0aa89e
A001733
7 in base 10-n.
[ "7", "7", "7", "10", "11", "12", "13", "21", "111", "1111111" ]
[ "fini", "nonn", "base", "full" ]
7
0
5
null
null
N. J. A. Sloane
2022-02-03T22:49:33
oeisdata/seq/A001/A001733.seq
c4597bbdfa2358ee49ab06149956c7ab
A001734
6 in base 10-n.
[ "6", "6", "6", "6", "10", "11", "12", "20", "110", "111111" ]
[ "fini", "nonn", "base", "full" ]
7
0
5
null
null
N. J. A. Sloane
2022-02-03T22:49:46
oeisdata/seq/A001/A001734.seq
1748b18fc33d8f712058a04131f71b5d
A001735
5 in base 10-n.
[ "5", "5", "5", "5", "5", "10", "11", "12", "101", "11111" ]
[ "fini", "nonn", "base", "full" ]
7
0
5
null
null
N. J. A. Sloane
2022-02-03T22:49:58
oeisdata/seq/A001/A001735.seq
3340d3a809274ec3eff98f26eab5c590
A001736
4 in base 10-n.
[ "4", "4", "4", "4", "4", "4", "10", "11", "100", "1111" ]
[ "fini", "nonn", "base", "full" ]
7
0
5
null
null
N. J. A. Sloane
2022-02-03T22:50:11
oeisdata/seq/A001/A001736.seq
8a613996a011c374b04c940c00295657
A001737
Squares written in base 2.
[ "0", "1", "100", "1001", "10000", "11001", "100100", "110001", "1000000", "1010001", "1100100", "1111001", "10010000", "10101001", "11000100", "11100001", "100000000", "100100001", "101000100", "101101001", "110010000", "110111001", "111100100", "1000010001", "1001000000", "1001110001", "1010100100", "1011011001" ]
[ "base", "easy", "nonn" ]
27
0
5
[ "A000290", "A001737", "A007088", "A159918" ]
null
N. J. A. Sloane
2022-02-01T07:12:23
oeisdata/seq/A001/A001737.seq
30cd86ffc08ed38e0be1a8b700b6bf5d
A001738
a(n) = n^2 written in base 3.
[ "0", "1", "11", "100", "121", "221", "1100", "1211", "2101", "10000", "10201", "11111", "12100", "20021", "21021", "22100", "100111", "101201", "110000", "111101", "112211", "121100", "122221", "201121", "210100", "212011", "221001", "1000000", "1002001", "1011011", "1020100", "1022121", "1101221", "1111100", "1120211" ]
[ "base", "easy", "nonn" ]
22
0
5
[ "A000290", "A001738", "A007089" ]
null
N. J. A. Sloane
2022-02-02T07:24:07
oeisdata/seq/A001/A001738.seq
1d3096cf6daaffcb1a643c1e82f59672
A001739
Squares written in base 4.
[ "0", "1", "10", "21", "100", "121", "210", "301", "1000", "1101", "1210", "1321", "2100", "2221", "3010", "3201", "10000", "10201", "11010", "11221", "12100", "12321", "13210", "20101", "21000", "21301", "22210", "23121", "30100", "31021", "32010", "33001", "100000", "101001", "102010", "103021", "110100", "111121", "112210", "113301" ]
[ "base", "easy", "nonn" ]
19
0
5
null
null
N. J. A. Sloane
2022-02-03T22:50:27
oeisdata/seq/A001/A001739.seq
ddbdce5f63b68b313a5b621bf4d41fd5
A001740
Squares written in base 5.
[ "0", "1", "4", "14", "31", "100", "121", "144", "224", "311", "400", "441", "1034", "1134", "1241", "1400", "2011", "2124", "2244", "2421", "3100", "3231", "3414", "4104", "4301", "10000", "10201", "10404", "11114", "11331", "12100", "12321", "13044", "13324", "14111", "14400", "20141", "20434", "21234", "22041", "22400", "23211", "24024" ]
[ "base", "easy", "nonn" ]
17
0
5
null
null
N. J. A. Sloane
2022-02-03T22:50:41
oeisdata/seq/A001/A001740.seq
3b81528bce77e8aef86c84df3f75882f
A001741
Squares written in base 6.
[ "0", "1", "4", "13", "24", "41", "100", "121", "144", "213", "244", "321", "400", "441", "524", "1013", "1104", "1201", "1300", "1401", "1504", "2013", "2124", "2241", "2400", "2521", "3044", "3213", "3344", "3521", "4100", "4241", "4424", "5013", "5204", "5401", "10000", "10201", "10404", "11013", "11224", "11441", "12100", "12321", "12544" ]
[ "base", "easy", "nonn" ]
19
0
5
null
null
N. J. A. Sloane
2022-02-03T22:50:54
oeisdata/seq/A001/A001741.seq
9ca2db3187600a0355b9a7575854c848
A001742
Numbers whose digits contain no loops (version 2).
[ "1", "2", "3", "5", "7", "11", "12", "13", "15", "17", "21", "22", "23", "25", "27", "31", "32", "33", "35", "37", "51", "52", "53", "55", "57", "71", "72", "73", "75", "77", "111", "112", "113", "115", "117", "121", "122", "123", "125", "127", "131", "132", "133", "135", "137", "151", "152", "153", "155", "157", "171", "172", "173", "175", "177", "211", "212", "213", "215" ]
[ "base", "nonn", "easy" ]
49
0
5
[ "A001729", "A001742", "A001743", "A001744", "A014261", "A014263", "A029581", "A046034", "A084545", "A084984", "A190222", "A190223", "A202267", "A202268" ]
null
N. J. A. Sloane
2024-07-30T01:53:57
oeisdata/seq/A001/A001742.seq
b98552bd6ee6290dd3d46367c25357f1
A001743
Numbers in which every digit contains at least one loop (version 1).
[ "0", "6", "8", "9", "60", "66", "68", "69", "80", "86", "88", "89", "90", "96", "98", "99", "600", "606", "608", "609", "660", "666", "668", "669", "680", "686", "688", "689", "690", "696", "698", "699", "800", "806", "808", "809", "860", "866", "868", "869", "880", "886", "888", "889", "890", "896", "898", "899", "900", "906", "908", "909", "960", "966", "968", "969" ]
[ "base", "nonn", "easy" ]
37
0
5
[ "A001743", "A001744", "A007090", "A014261", "A014263", "A017042", "A029581", "A046034", "A084984", "A202267", "A202268" ]
null
N. J. A. Sloane
2022-11-16T14:54:00
oeisdata/seq/A001/A001743.seq
82327bab4542d149a742bcf00d412c66
A001744
Numbers n such that every digit contains a loop (version 2).
[ "0", "4", "6", "8", "9", "40", "44", "46", "48", "49", "60", "64", "66", "68", "69", "80", "84", "86", "88", "89", "90", "94", "96", "98", "99", "400", "404", "406", "408", "409", "440", "444", "446", "448", "449", "460", "464", "466", "468", "469", "480", "484", "486", "488", "489", "490", "494", "496", "498", "499", "600", "604", "606", "608", "609", "640", "644", "646" ]
[ "base", "nonn", "easy" ]
36
0
5
[ "A001743", "A001744", "A007091", "A014261", "A014263", "A017042", "A029581", "A046034", "A061371", "A084544", "A084984", "A202267", "A202268" ]
null
N. J. A. Sloane
2019-09-09T10:58:00
oeisdata/seq/A001/A001744.seq
835e3749f3075ed84e69d73c59657e7d
A001745
Numbers such that at least one digit contains a loop (version 2). Also called "holey" or "holy" numbers.
[ "0", "4", "6", "8", "9", "10", "14", "16", "18", "19", "20", "24", "26", "28", "29", "30", "34", "36", "38", "39", "40", "41", "42", "43", "44", "45", "46", "47", "48", "49", "50", "54", "56", "58", "59", "60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "70", "74", "76", "78", "79", "80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "90", "91", "92", "93", "94", "95" ]
[ "base", "nonn" ]
16
0
5
null
null
N. J. A. Sloane
2021-12-23T22:49:18
oeisdata/seq/A001/A001745.seq
357c3863cdb11a8a68522624bc1d5e4e
A001746
At least one digit contains a loop (version 1).
[ "0", "6", "8", "9", "10", "16", "18", "19", "20", "26", "28", "29", "30", "36", "38", "39", "40", "46", "48", "49", "50", "56", "58", "59", "60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "70", "76", "78", "79", "80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "90", "91", "92", "93", "94", "95", "96", "97", "98", "99", "100", "101", "102", "103", "104", "105" ]
[ "base", "nonn", "easy" ]
15
0
5
null
null
N. J. A. Sloane
2022-02-01T01:26:00
oeisdata/seq/A001/A001746.seq
4d2eaab348c5c97aaa09586740b62c42
A001747
2 together with primes multiplied by 2.
[ "2", "4", "6", "10", "14", "22", "26", "34", "38", "46", "58", "62", "74", "82", "86", "94", "106", "118", "122", "134", "142", "146", "158", "166", "178", "194", "202", "206", "214", "218", "226", "254", "262", "274", "278", "298", "302", "314", "326", "334", "346", "358", "362", "382", "386", "394", "398", "422", "446", "454", "458", "466", "478", "482", "502" ]
[ "nonn", "easy", "nice" ]
51
0
5
[ "A001747", "A009530", "A060679", "A098764", "A100484" ]
null
N. J. A. Sloane
2024-11-29T15:02:51
oeisdata/seq/A001/A001747.seq
9fa7ceced8ae8c294c22c4a5f905a7af
A001748
a(n) = 3 * prime(n).
[ "6", "9", "15", "21", "33", "39", "51", "57", "69", "87", "93", "111", "123", "129", "141", "159", "177", "183", "201", "213", "219", "237", "249", "267", "291", "303", "309", "321", "327", "339", "381", "393", "411", "417", "447", "453", "471", "489", "501", "519", "537", "543", "573", "579", "591", "597", "633", "669", "681", "687", "699", "717", "723", "753" ]
[ "nonn", "easy" ]
67
0
5
[ "A000040", "A001358", "A001748", "A100484", "A164023", "A164024", "A179545", "A253046" ]
null
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001748.seq
992b215fd5698edde44727da961fa262
A001749
Primes multiplied by 4.
[ "8", "12", "20", "28", "44", "52", "68", "76", "92", "116", "124", "148", "164", "172", "188", "212", "236", "244", "268", "284", "292", "316", "332", "356", "388", "404", "412", "428", "436", "452", "508", "524", "548", "556", "596", "604", "628", "652", "668", "692", "716", "724", "764", "772", "788", "796", "844", "892", "908", "916", "932", "956", "964", "1004", "1028", "1052", "1076", "1084", "1108", "1124", "1132", "1172", "1228", "1244", "1252" ]
[ "nonn", "easy" ]
52
0
5
[ "A000040", "A001749", "A003415", "A048272" ]
null
N. J. A. Sloane
2024-02-19T01:48:03
oeisdata/seq/A001/A001749.seq
3483524ad017ebeb55e258b274527d3b
A001750
Primes multiplied by 5.
[ "10", "15", "25", "35", "55", "65", "85", "95", "115", "145", "155", "185", "205", "215", "235", "265", "295", "305", "335", "355", "365", "395", "415", "445", "485", "505", "515", "535", "545", "565", "635", "655", "685", "695", "745", "755", "785", "815", "835", "865", "895", "905", "955", "965", "985", "995", "1055", "1115", "1135", "1145", "1165", "1195" ]
[ "nonn", "easy" ]
28
0
5
[ "A000040", "A001750" ]
null
N. J. A. Sloane
2024-02-05T00:52:49
oeisdata/seq/A001/A001750.seq
4676fcecbf9241bb4f11bc75da356b0d
A001751
Primes together with primes multiplied by 2.
[ "2", "3", "4", "5", "6", "7", "10", "11", "13", "14", "17", "19", "22", "23", "26", "29", "31", "34", "37", "38", "41", "43", "46", "47", "53", "58", "59", "61", "62", "67", "71", "73", "74", "79", "82", "83", "86", "89", "94", "97", "101", "103", "106", "107", "109", "113", "118", "122", "127", "131", "134", "137", "139", "142", "146", "149", "151", "157", "158", "163", "166" ]
[ "nonn", "easy" ]
40
0
5
[ "A000040", "A001747", "A001751", "A026741", "A033948", "A039698", "A046079", "A178156", "A251561", "A264828" ]
null
N. J. A. Sloane
2024-10-17T12:52:16
oeisdata/seq/A001/A001751.seq
b45e9ecfeec4b826fd39e269d6421952
A001752
Expansion of 1/((1+x)*(1-x)^5).
[ "1", "4", "11", "24", "46", "80", "130", "200", "295", "420", "581", "784", "1036", "1344", "1716", "2160", "2685", "3300", "4015", "4840", "5786", "6864", "8086", "9464", "11011", "12740", "14665", "16800", "19160", "21760", "24616", "27744", "31161", "34884", "38931", "43320", "48070", "53200", "58730", "64680", "71071", "77924", "85261" ]
[ "nonn", "easy" ]
97
0
5
[ "A000217", "A000292", "A000332", "A000929", "A001752", "A001753", "A002620", "A002623", "A004526", "A010751", "A056885", "A057524", "A108561", "A152205", "A158454", "A169792", "A216172", "A216173", "A216175" ]
null
N. J. A. Sloane
2024-01-19T04:33:05
oeisdata/seq/A001/A001752.seq
28304c35737b32619183a66fff408a13
A001753
Expansion of 1/((1+x)*(1-x)^6).
[ "1", "5", "16", "40", "86", "166", "296", "496", "791", "1211", "1792", "2576", "3612", "4956", "6672", "8832", "11517", "14817", "18832", "23672", "29458", "36322", "44408", "53872", "64883", "77623", "92288", "109088", "128248", "150008", "174624", "202368", "233529" ]
[ "nonn", "easy" ]
46
0
5
[ "A000217", "A001752", "A001753", "A001769", "A002620", "A008804", "A038163", "A054343", "A169793" ]
null
N. J. A. Sloane
2024-01-18T09:52:25
oeisdata/seq/A001/A001753.seq
ca9c89affb4fd8ee26cbd12269d9d098
A001754
Lah numbers: a(n) = n!*binomial(n-1,2)/6.
[ "0", "0", "1", "12", "120", "1200", "12600", "141120", "1693440", "21772800", "299376000", "4390848000", "68497228800", "1133317785600", "19833061248000", "366148823040000", "7113748561920000", "145120470663168000", "3101950060425216000", "69337707233034240000", "1617879835437465600000" ]
[ "nonn", "easy" ]
48
0
5
[ "A001113", "A001620", "A001754", "A005990", "A008297", "A053495", "A091725", "A099285", "A111596", "A260665" ]
[ "M4863", "N2079" ]
N. J. A. Sloane
2024-05-01T09:00:55
oeisdata/seq/A001/A001754.seq
d69211fa9434db424538b4cf80c60380
A001755
Lah numbers: a(n) = n! * binomial(n-1, 3)/4!.
[ "1", "20", "300", "4200", "58800", "846720", "12700800", "199584000", "3293136000", "57081024000", "1038874636800", "19833061248000", "396661224960000", "8299373322240000", "181400588328960000", "4135933413900288000", "98228418580131840000", "2426819753156198400000", "62288373664342425600000" ]
[ "nonn", "easy" ]
35
0
5
[ "A001113", "A001620", "A001755", "A008297", "A053495", "A091725", "A099285", "A111596" ]
[ "M5096", "N2207" ]
N. J. A. Sloane
2022-05-02T02:58:56
oeisdata/seq/A001/A001755.seq
07aa9266bfccfae937984ff43ccb1797
A001756
a(n) = A059366(n,n-3) = A059366(n,3) for n >= 3, where the triangle A059366 arises from the expansion of a trigonometric integral.
[ "15", "60", "450", "4500", "55125", "793800", "13097700", "243243000", "5016886875", "113716102500", "2808787731750", "75071235739500", "2158298027510625", "66409170077250000", "2177272076104125000", "75769068248423550000", "2789248824895091934375", "108288483790044745687500" ]
[ "nonn" ]
45
0
5
[ "A001147", "A001756", "A007531", "A059366" ]
[ "M4967", "N2131" ]
N. J. A. Sloane
2020-05-13T08:50:09
oeisdata/seq/A001/A001756.seq
b11bac28202bd118fbf8495112eb1c4b
A001757
Expansion of an integral: central elements of rows of triangle in A059366.
[ "1", "1", "2", "9", "54", "450", "4500", "55125", "771750", "12502350", "225042300", "4538353050", "99843767100", "2410513805700", "62673358948200", "1762688220418125", "52880646612543750", "1698056319002793750", "57733914846094987500", "2084194325944029048750" ]
[ "nonn", "easy" ]
29
0
5
[ "A000079", "A000142", "A000984", "A001757", "A059366", "A283678" ]
[ "M1941", "N0769" ]
N. J. A. Sloane
2022-02-01T01:20:06
oeisdata/seq/A001/A001757.seq
5b0813b5ac8f38dc2d60655ce7d9f590
A001758
Number of quasi-alternating permutations of length n.
[ "0", "2", "12", "58", "300", "1682", "10332", "69298", "505500", "3990362", "33925452", "309248938", "3010070700", "31167995042", "342164637372", "3970297978978", "48558251523900", "624386836023722", "8421511353298092", "118891756573779418", "1753452275441153100", "26967372781086764402" ]
[ "nonn", "easy", "nice" ]
101
0
5
[ "A000708", "A001250", "A001758", "A001759", "A001760", "A008970", "A059427" ]
[ "M2027", "N0800" ]
N. J. A. Sloane
2024-07-30T01:49:44
oeisdata/seq/A001/A001758.seq
0ac5ab1640321efdefbceb169e1b35d7
A001759
Number of permutations of [n] with n-3 sequences.
[ "2", "28", "236", "1852", "14622", "119964", "1034992", "9434444", "90968602", "927367340", "9982234068", "113261721276", "1352111669942", "16950982295356", "222752212005464", "3062768908594348", "43987314357078642", "658804420084315212" ]
[ "nonn" ]
26
0
5
[ "A001250", "A001758", "A001759" ]
[ "M2150", "N0857" ]
N. J. A. Sloane
2014-12-24T19:54:55
oeisdata/seq/A001/A001759.seq
dfe18aa61e25ec2e69c7adbbbd51d932
A001760
Number of permutations of [n] with n-4 sequences.
[ "2", "60", "836", "9576", "103326", "1106820", "12062152", "135391872", "1575253690", "19058801580", "240134763948", "3152151344088", "43098592576694", "613444153400340", "9082400109162224", "139747529003597424", "2232451845925297938" ]
[ "nonn" ]
20
0
5
[ "A001758", "A001759", "A001760" ]
[ "M2176", "N0870" ]
N. J. A. Sloane
2014-12-24T19:55:03
oeisdata/seq/A001/A001760.seq
892e5af18d60cbcd3cc425ca1c2423a3
A001761
a(n) = (2*n)!/(n+1)!.
[ "1", "1", "4", "30", "336", "5040", "95040", "2162160", "57657600", "1764322560", "60949324800", "2346549004800", "99638080819200", "4626053752320000", "233153109116928000", "12677700308232960000", "739781100339240960000", "46113021921146019840000" ]
[ "nonn" ]
101
0
5
[ "A000108", "A001761", "A001813", "A006963", "A173333", "A255982", "A256061" ]
[ "M3635", "N1478" ]
N. J. A. Sloane
2024-02-20T00:57:42
oeisdata/seq/A001/A001761.seq
c06e366f19f28a5109622d25f4abc2ed
A001762
Number of labeled n-vertex dissections of a ball.
[ "1", "1", "10", "180", "4620", "152880", "6168960", "293025600", "15990004800", "984647664000", "67493121696000", "5094263446272000", "419688934689024000", "37465564582397952000", "3601861863990534144000", "370962724717928318976000", "40744403224500159055872000" ]
[ "nonn" ]
44
0
5
[ "A000407", "A001762", "A001763", "A001764", "A027610" ]
[ "M4741", "N2029" ]
N. J. A. Sloane
2024-03-27T21:00:20
oeisdata/seq/A001/A001762.seq
9de3b0b5720a95f59a169331f8b96893
A001763
a(n) = (3n+3)!/(2n+3)!.
[ "1", "1", "6", "72", "1320", "32760", "1028160", "39070080", "1744364160", "89513424000", "5191778592000", "335885501952000", "23982224839372800", "1873278229119897600", "158905670470170624000", "14547557832075620352000", "1429628183315795054592000", "150110959248158480732160000" ]
[ "nonn" ]
47
0
5
[ "A001762", "A001763" ]
[ "M4279", "N1788" ]
N. J. A. Sloane
2024-02-25T11:07:52
oeisdata/seq/A001/A001763.seq
284138d5b8227bef8c98ca82b595423c
A001764
a(n) = binomial(3*n,n)/(2*n+1) (enumerates ternary trees and also noncrossing trees).
[ "1", "1", "3", "12", "55", "273", "1428", "7752", "43263", "246675", "1430715", "8414640", "50067108", "300830572", "1822766520", "11124755664", "68328754959", "422030545335", "2619631042665", "16332922290300", "102240109897695", "642312451217745", "4048514844039120", "25594403741131680", "162250238001816900" ]
[ "easy", "nonn", "nice", "core", "changed" ]
715
0
5
[ "A000108", "A001762", "A001763", "A001764", "A002293", "A002294", "A002296", "A005034", "A005036", "A006013", "A007173", "A025174", "A027610", "A047749", "A047761", "A062993", "A063548", "A064017", "A072247", "A072248", "A102537", "A108410", "A108767", "A113047", "A130564", "A134264", "A143603", "A188687", "A256311", "A258708", "A346628", "A369315", "A371350", "A371351" ]
[ "M2926", "N1174" ]
N. J. A. Sloane
2025-04-18T13:03:30
oeisdata/seq/A001/A001764.seq
e7aed74484439ebf9ae370b1460d0c04
A001765
Coefficients of iterated exponentials.
[ "1", "7", "77", "1155", "21973", "506989", "13761937", "429853851", "15192078027", "599551077881", "26140497946017", "1248134313062231", "64783855286002573", "3632510833677434324", "218845138322691595694", "14099918095287618382033", "967508237903439910445565", "70447525748137979196484589" ]
[ "nonn", "easy" ]
33
0
5
[ "A000268", "A000310", "A000359", "A000406", "A001765", "A003713" ]
[ "M4447", "N1882" ]
N. J. A. Sloane
2023-01-07T14:48:25
oeisdata/seq/A001/A001765.seq
e0c1b242487d90a0d7565423c54465b3
A001766
Index of (the image of) the modular group Gamma(n) in PSL_2(Z).
[ "1", "6", "12", "24", "60", "72", "168", "192", "324", "360", "660", "576", "1092", "1008", "1440", "1536", "2448", "1944", "3420", "2880", "4032", "3960", "6072", "4608", "7500", "6552", "8748", "8064", "12180", "8640", "14880", "12288", "15840", "14688", "20160", "15552", "25308", "20520", "26208", "23040", "34440", "24192", "39732", "31680" ]
[ "nonn", "easy" ]
31
0
5
[ "A000056", "A001766" ]
[ "M4098", "N1700" ]
N. J. A. Sloane
2019-10-24T11:17:15
oeisdata/seq/A001/A001766.seq
3c45111b1b2ba3ca417077ed47df82ea
A001767
Genus of modular group Gamma(n) = genus of modular curve Chi(n).
[ "0", "0", "0", "0", "1", "3", "5", "10", "13", "26", "25", "50", "49", "73", "81", "133", "109", "196", "169", "241", "241", "375", "289", "476", "421", "568", "529", "806", "577", "1001", "833", "1081", "1009", "1393", "1081", "1768", "1441", "1849", "1633", "2451", "1729", "2850", "2281", "2809", "2641", "3773", "2689", "4215", "3301", "4321", "3865", "5500" ]
[ "nonn", "easy" ]
38
0
5
null
[ "M2459", "N0976" ]
N. J. A. Sloane
2019-10-23T11:09:57
oeisdata/seq/A001/A001767.seq
e8e62c525da6795c3a2298f3aa270bab
A001768
Sorting numbers: number of comparisons for merge insertion sort of n elements.
[ "0", "1", "3", "5", "7", "10", "13", "16", "19", "22", "26", "30", "34", "38", "42", "46", "50", "54", "58", "62", "66", "71", "76", "81", "86", "91", "96", "101", "106", "111", "116", "121", "126", "131", "136", "141", "146", "151", "156", "161", "166", "171", "177", "183", "189", "195", "201", "207", "213", "219", "225", "231", "237", "243", "249", "255" ]
[ "nonn", "easy", "nice" ]
53
0
5
[ "A000523", "A001768", "A085423" ]
[ "M2408", "N0954" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001768.seq
f1db17b6d56817a9b76f2b4ae7d49593
A001769
Expansion of 1/((1+x)*(1-x)^7).
[ "1", "6", "22", "62", "148", "314", "610", "1106", "1897", "3108", "4900", "7476", "11088", "16044", "22716", "31548", "43065", "57882", "76714", "100386", "129844", "166166", "210574", "264446", "329329", "406952", "499240", "608328", "736576", "886584", "1061208", "1263576", "1497105", "1765518", "2072862", "2423526", "2822260", "3274194", "3784858" ]
[ "nonn", "easy" ]
45
0
5
[ "A001752", "A001753", "A001769", "A001779", "A002620", "A002623", "A158454", "A169794" ]
null
N. J. A. Sloane
2024-01-18T09:51:19
oeisdata/seq/A001/A001769.seq
7af420b27846fdb7662bd1ae433b7887
A001770
Numbers k such that 5*2^k - 1 is prime.
[ "2", "4", "8", "10", "12", "14", "18", "32", "48", "54", "72", "148", "184", "248", "270", "274", "420", "1340", "1438", "1522", "1638", "1754", "1884", "2014", "2170", "2548", "2622", "2652", "2704", "13510", "21738", "25624", "41934", "51478", "52540", "53230", "172300", "245728", "350028", "1194164" ]
[ "nonn", "nice", "hard", "more" ]
39
0
5
[ "A001770", "A002254", "A050522" ]
[ "M1087", "N0415" ]
N. J. A. Sloane.
2018-12-22T14:40:44
oeisdata/seq/A001/A001770.seq
f83b45c33ccd9604105c7a161f70045a
A001771
Numbers k such that 7*2^k - 1 is prime.
[ "1", "5", "9", "17", "21", "29", "45", "177", "18381", "22529", "24557", "26109", "34857", "41957", "67421", "70209", "169085", "173489", "177977", "363929", "372897" ]
[ "hard", "nonn", "more" ]
37
0
5
[ "A001771", "A002235", "A003307", "A005541", "A032353", "A046865", "A046866", "A046867", "A050523", "A056725", "A079906", "A079907" ]
[ "M3784", "N1541" ]
N. J. A. Sloane
2023-11-06T14:58:26
oeisdata/seq/A001/A001771.seq
796262a818ec28e28a3ef29a5471030c
A001772
Numbers k such that 11*2^k - 1 is prime.
[ "2", "26", "50", "54", "126", "134", "246", "354", "362", "950", "1310", "2498", "6926", "11826", "31734", "67850", "74726", "96150", "374114", "696438", "743322", "1044086", "1104606", "1261478" ]
[ "hard", "nonn", "nice", "more" ]
43
0
5
[ "A001772", "A002261", "A050525" ]
[ "M2145", "N0854" ]
N. J. A. Sloane
2023-11-06T14:58:04
oeisdata/seq/A001/A001772.seq
b6584029045805d5c4df9325428c16a3
A001773
Numbers k such that 13*2^k - 1 is prime.
[ "3", "7", "23", "287", "291", "795", "2203", "5711", "7927", "9443", "10095", "19071", "29611", "34651", "51875", "55343", "77511", "166303", "233207" ]
[ "hard", "nonn", "more" ]
40
0
5
[ "A001773", "A032356" ]
[ "M2686", "N1076" ]
N. J. A. Sloane
2023-11-06T14:59:00
oeisdata/seq/A001/A001773.seq
ad0979b83ba5ab195e31edb9c81fe38d
A001774
Numbers k such that 17*2^k - 1 is prime.
[ "2", "4", "6", "16", "20", "36", "54", "60", "96", "124", "150", "252", "356", "460", "612", "654", "664", "698", "702", "972", "1188", "1312", "3062", "4214", "4288", "5280", "9100", "20262", "21676", "24828", "46144", "62148", "79974", "117784", "211464", "310744", "310754", "429318", "601158", "605394" ]
[ "hard", "nonn" ]
38
0
5
null
[ "M1028", "N0387" ]
N. J. A. Sloane
2023-11-06T15:01:41
oeisdata/seq/A001/A001774.seq
653670457e6fe90dbe186b232cd6fd73
A001775
Numbers k such that 19*2^k - 1 is prime.
[ "1", "3", "5", "21", "41", "49", "89", "133", "141", "165", "189", "293", "305", "395", "651", "665", "771", "801", "923", "953", "3689", "5315", "6989", "15641", "48819", "78389", "134053", "167843", "181395", "311091", "353661", "645555", "916763" ]
[ "nonn", "hard", "more" ]
38
0
5
[ "A001775", "A032359" ]
[ "M2506", "N0991" ]
N. J. A. Sloane
2023-11-06T14:54:35
oeisdata/seq/A001/A001775.seq
25072ec969712cdcb348f6de41407c46
A001776
Dimensions of the Jordan operad.
[ "1", "1", "3", "11", "55", "330", "2345", "19089", "175203", "1785840" ]
[ "nonn", "nice", "more" ]
40
0
5
null
[ "M2906", "N1167" ]
N. J. A. Sloane
2025-03-30T15:36:01
oeisdata/seq/A001/A001776.seq
854ccbe060f2df6e821160c7b4e85c71
A001777
Lah numbers: a(n) = n! * binomial(n-1, 4)/5!.
[ "1", "30", "630", "11760", "211680", "3810240", "69854400", "1317254400", "25686460800", "519437318400", "10908183686400", "237996734976000", "5394592659456000", "126980411830272000", "3101950060425216000", "78582734864105472000", "2062796790182768640000", "56059536297908183040000" ]
[ "nonn", "easy" ]
26
0
5
[ "A001113", "A001620", "A001777", "A008297", "A053495", "A091725", "A099285", "A111596" ]
[ "M5213", "N2267" ]
N. J. A. Sloane
2022-05-02T02:59:10
oeisdata/seq/A001/A001777.seq
2e0ef615de1c2ee13f3cb7513c9b2054
A001778
Lah numbers: a(n) = n!*binomial(n-1,5)/6!.
[ "1", "42", "1176", "28224", "635040", "13970880", "307359360", "6849722880", "155831195520", "3636061228800", "87265469491200", "2157837063782400", "55024845126451200", "1447576694865100800", "39291367432052736000", "1100158288097476608000", "31767070568814637056000" ]
[ "nonn", "easy" ]
34
0
5
[ "A001113", "A001620", "A001778", "A008297", "A091725", "A099285", "A111596" ]
[ "M5279", "N2297" ]
N. J. A. Sloane
2022-05-02T08:32:23
oeisdata/seq/A001/A001778.seq
16dc47163097c801066512e1823cfeaf
A001779
Expansion of 1/((1+x)(1-x)^8).
[ "1", "7", "29", "91", "239", "553", "1163", "2269", "4166", "7274", "12174", "19650", "30738", "46782", "69498", "101046", "144111", "201993", "278707", "379093", "508937", "675103", "885677", "1150123", "1479452", "1886404", "2385644", "2993972" ]
[ "nonn", "easy" ]
38
0
5
[ "A001769", "A001779", "A169795" ]
null
N. J. A. Sloane
2024-01-18T09:49:58
oeisdata/seq/A001/A001779.seq
e685a71eecbc60d36448e3c8e1302b5f
A001780
Expansion of 1/((1+x)(1-x)^9).
[ "1", "8", "37", "128", "367", "920", "2083", "4352", "8518", "15792", "27966", "47616", "78354", "125136", "194634", "295680", "439791", "641784", "920491", "1299584", "1808521", "2483624", "3369301", "4519424", "5998876", "7885280", "10270924", "13264896" ]
[ "nonn", "easy" ]
32
0
5
[ "A001769", "A001779", "A001780", "A158454", "A169796" ]
null
N. J. A. Sloane
2024-01-18T09:48:12
oeisdata/seq/A001/A001780.seq
f2fff9364d27bbde98bf3f063df14e2d
A001781
Expansion of 1/((1+x)*(1-x)^10).
[ "1", "9", "46", "174", "541", "1461", "3544", "7896", "16414", "32206", "60172", "107788", "186142", "311278", "505912", "801592", "1241383", "1883167", "2803658", "4103242", "5911763", "8395387", "11764688", "16284112", "22282988", "30168268", "40439192", "53704088", "70699532", "92312108", "119603024", "153835856", "196507709", "249384101" ]
[ "nonn", "easy", "changed" ]
27
0
5
[ "A000582", "A001781", "A112465" ]
null
N. J. A. Sloane
2025-04-21T10:46:22
oeisdata/seq/A001/A001781.seq
790cc80a35b69b374de914e8680e1ca8
A001782
Discriminants of Shapiro polynomials.
[ "1", "-44", "-4940800", "-564083990621761115783168", "-265595429519150677725101890892978815884074732203939261150723571712" ]
[ "sign", "nice" ]
40
0
5
[ "A001782", "A020985", "A331691" ]
[ "M5286", "N2301" ]
N. J. A. Sloane.
2020-04-23T20:42:36
oeisdata/seq/A001/A001782.seq
1cf7a80b5536f37dcd0ff260a0113cd0
A001783
n-phi-torial, or phi-torial of n: Product k, 1 <= k <= n, k relatively prime to n.
[ "1", "1", "2", "3", "24", "5", "720", "105", "2240", "189", "3628800", "385", "479001600", "19305", "896896", "2027025", "20922789888000", "85085", "6402373705728000", "8729721", "47297536000", "1249937325", "1124000727777607680000", "37182145", "41363226782215962624", "608142583125", "1524503639859200000" ]
[ "nonn", "nice", "easy" ]
113
0
5
[ "A001783", "A023896", "A038566", "A066570", "A124441", "A216919" ]
[ "M0921", "N0346" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001783.seq
8c455243073dbe4f0c73a585df2c9d0c
A001784
Second-order reciprocal Stirling number (Fekete) a(n) = [[2n+3, n]]. The number of n-orbit permutations of a (2n+3)-set with at least 2 elements in each orbit. Also known as associated Stirling numbers of the first kind (e.g., Comtet).
[ "1", "24", "924", "26432", "705320", "18858840", "520059540", "14980405440", "453247114320", "14433720701400", "483908513388300", "17068210823664000", "632607429473019000", "24602295329058447000", "1002393959071727722500", "42720592574082543120000" ]
[ "nonn" ]
60
0
5
[ "A000483", "A000907", "A001784", "A001785" ]
[ "M5169", "N2244" ]
N. J. A. Sloane
2025-03-23T08:39:58
oeisdata/seq/A001/A001784.seq
c410b0f350df97320ebd1b9c1ee64bea
A001785
Second-order reciprocal Stirling number (Fekete) a(n) = [[2n+4, n]]. The number of n-orbit permutations of a (2n+4)-set with at least 2 elements in each orbit. Also known as associated Stirling numbers of the first kind (e.g., Comtet).
[ "1", "120", "7308", "303660", "11098780", "389449060", "13642629000", "486591585480", "17856935296200", "678103775949600", "26726282654771700", "1094862336960892500", "46641683693715610500", "2066075391660447667500", "95122549872697437090000" ]
[ "nonn" ]
64
0
5
[ "A000483", "A000907", "A001784", "A001785" ]
[ "M5382", "N2338" ]
N. J. A. Sloane
2023-08-05T13:08:47
oeisdata/seq/A001/A001785.seq
9a9267e863bdce03d8f788b2044b30d8
A001786
Expansion of 1/((1+x)*(1-x)^11).
[ "1", "10", "56", "230", "771", "2232", "5776", "13672", "30086", "62292", "122464", "230252", "416394", "727672", "1233584", "2035176", "3276559", "5159726", "7963384", "12066626", "17978389", "26373776", "38138464", "54422576", "76705564", "106873832", "147313024", "201017112", "271716644", "364028752", "483631776", "637467632", "833975341" ]
[ "nonn", "easy", "changed" ]
35
0
5
[ "A001780", "A001786", "A112465", "A158454" ]
null
N. J. A. Sloane
2025-04-21T10:46:26
oeisdata/seq/A001/A001786.seq
fe95daf8d0599a08746da6541deea4bc
A001787
a(n) = n*2^(n-1).
[ "0", "1", "4", "12", "32", "80", "192", "448", "1024", "2304", "5120", "11264", "24576", "53248", "114688", "245760", "524288", "1114112", "2359296", "4980736", "10485760", "22020096", "46137344", "96468992", "201326592", "419430400", "872415232", "1811939328", "3758096384", "7784628224", "16106127360", "33285996544" ]
[ "nonn", "easy", "nice" ]
388
0
5
[ "A000079", "A000337", "A001787", "A001788", "A001789", "A001792", "A002064", "A003506", "A003945", "A016777", "A027471", "A038207", "A053109", "A058922", "A059260", "A059670", "A085750", "A090802", "A097067", "A118442", "A130300", "A134083", "A167591", "A212697", "A263646", "A322427", "A322428" ]
[ "M3444", "N1398" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001787.seq
c926bb03b372fb71a458b793b044216e
A001788
a(n) = n*(n+1)*2^(n-2).
[ "0", "1", "6", "24", "80", "240", "672", "1792", "4608", "11520", "28160", "67584", "159744", "372736", "860160", "1966080", "4456448", "10027008", "22413312", "49807360", "110100480", "242221056", "530579456", "1157627904", "2516582400", "5452595200", "11777605632", "25367150592", "54492397568", "116769423360", "249644974080", "532575944704" ]
[ "nonn", "easy", "nice" ]
223
0
5
[ "A000079", "A000217", "A001787", "A001788", "A001789", "A001793", "A001844", "A027472", "A027474", "A027476", "A038207", "A038845", "A081135", "A081136", "A081138", "A081139", "A081140", "A081141", "A081142", "A094305", "A290031" ]
[ "M4161", "N1729" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001788.seq
0283034c580fbf2a618f1dcaffd2ce0f
A001789
a(n) = binomial(n,3)*2^(n-3).
[ "1", "8", "40", "160", "560", "1792", "5376", "15360", "42240", "112640", "292864", "745472", "1863680", "4587520", "11141120", "26738688", "63504384", "149422080", "348651520", "807403520", "1857028096", "4244635648", "9646899200", "21810380800", "49073356800", "109924319232" ]
[ "nonn", "easy", "nice" ]
113
0
5
[ "A000079", "A001787", "A001788", "A001789", "A003472", "A007318", "A038207", "A080930", "A082138" ]
[ "M4522", "N1916" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001789.seq
ba84f8948247d1bd1673c6f5e6160f1b
A001790
Numerators in expansion of 1/sqrt(1-x).
[ "1", "1", "3", "5", "35", "63", "231", "429", "6435", "12155", "46189", "88179", "676039", "1300075", "5014575", "9694845", "300540195", "583401555", "2268783825", "4418157975", "34461632205", "67282234305", "263012370465", "514589420475", "8061900920775", "15801325804719" ]
[ "nonn", "easy", "nice", "frac", "changed" ]
246
0
5
[ "A000142", "A000984", "A001147", "A001316", "A001405", "A001790", "A001800", "A001801", "A001803", "A002596", "A005187", "A007814", "A008316", "A036069", "A046161", "A056040", "A060818", "A061548", "A061549", "A063079", "A086117", "A094638", "A100258", "A101926", "A123854", "A161198", "A161199", "A161200", "A161201", "A161202", "A163590", "A180403", "A273194", "A344402" ]
[ "M2508", "N0992" ]
N. J. A. Sloane
2025-04-11T10:32:07
oeisdata/seq/A001/A001790.seq
522c12e9897beb9871066bcb3796f521
A001791
a(n) = binomial coefficient C(2n, n-1).
[ "0", "1", "4", "15", "56", "210", "792", "3003", "11440", "43758", "167960", "646646", "2496144", "9657700", "37442160", "145422675", "565722720", "2203961430", "8597496600", "33578000610", "131282408400", "513791607420", "2012616400080", "7890371113950", "30957699535776", "121548660036300", "477551179875952" ]
[ "nonn", "easy", "nice", "changed" ]
282
0
5
[ "A000070", "A000108", "A000302", "A000346", "A000984", "A001791", "A002054", "A002378", "A002390", "A008549", "A025566", "A032443", "A076540", "A088218", "A097805", "A100257", "A132812", "A163493", "A202736", "A345197", "A345910" ]
[ "M3500", "N1421" ]
N. J. A. Sloane
2025-04-24T15:14:21
oeisdata/seq/A001/A001791.seq
3af1e612e81a9402891a3ea847f58eca
A001792
a(n) = (n+2)*2^(n-1).
[ "1", "3", "8", "20", "48", "112", "256", "576", "1280", "2816", "6144", "13312", "28672", "61440", "131072", "278528", "589824", "1245184", "2621440", "5505024", "11534336", "24117248", "50331648", "104857600", "218103808", "452984832", "939524096", "1946157056", "4026531840", "8321499136", "17179869184", "35433480192" ]
[ "nonn", "easy", "nice" ]
441
0
5
[ "A000079", "A000108", "A000120", "A001700", "A001787", "A001792", "A003583", "A005043", "A007403", "A008949", "A030523", "A030528", "A039991", "A045623", "A049600", "A053113", "A053120", "A055248", "A091867", "A125092", "A128064", "A130584", "A164910", "A294435", "A294436" ]
[ "M2739", "N1100" ]
N. J. A. Sloane
2025-01-08T09:23:04
oeisdata/seq/A001/A001792.seq
b772110598e245b0e7ab247a0d66bd9c
A001793
a(n) = n*(n+3)*2^(n-3).
[ "1", "5", "18", "56", "160", "432", "1120", "2816", "6912", "16640", "39424", "92160", "212992", "487424", "1105920", "2490368", "5570560", "12386304", "27394048", "60293120", "132120576", "288358400", "627048448", "1358954496", "2936012800", "6325010432", "13589544960", "29125246976" ]
[ "easy", "nonn" ]
177
0
5
[ "A001793", "A039991", "A053120", "A055252", "A058396", "A058645" ]
[ "M3881", "N1591" ]
N. J. A. Sloane and Simon Plouffe
2024-03-31T17:26:02
oeisdata/seq/A001/A001793.seq
7f72dfe64589c67a94c4cd9db00d4427
A001794
Negated coefficients of Chebyshev T polynomials: [x^n](-T(n+6, x)), n >= 0.
[ "1", "7", "32", "120", "400", "1232", "3584", "9984", "26880", "70400", "180224", "452608", "1118208", "2723840", "6553600", "15597568", "36765696", "85917696", "199229440", "458752000", "1049624576", "2387607552", "5402263552", "12163481600", "27262976000", "60850962432" ]
[ "nonn", "easy" ]
112
0
5
[ "A001789", "A001794", "A005900", "A008310", "A028297", "A039991", "A053120", "A065097", "A081279" ]
[ "M4405", "N1859" ]
N. J. A. Sloane
2024-10-14T11:30:46
oeisdata/seq/A001/A001794.seq
85f452de3388e02389ca47be753baaf7
A001795
Coefficients of Legendre polynomials.
[ "1", "1", "7", "33", "715", "4199", "52003", "334305", "17678835", "119409675", "1641030105", "11435320455", "322476036831", "2295919134019", "32968493968795", "238436656380769", "27767032438524099", "203236010537432691", "2989949596465113373" ]
[ "nonn", "changed" ]
47
0
5
[ "A000108", "A001791", "A001795", "A002596", "A048990", "A065097", "A099024" ]
[ "M4407", "N1861" ]
N. J. A. Sloane
2025-04-23T04:50:17
oeisdata/seq/A001/A001795.seq
9a42d07ae6519c0ea2d0d7f744a3a50d
A001796
Coefficients of Legendre polynomials.
[ "1", "3", "27", "143", "3315", "20349", "260015", "1710855", "92116035", "631165425", "8775943605", "61750730457", "1755702867191", "12587970424449", "181858466731095", "1322239639929719", "154702037871777123", "1137023085979691001", "16789716964765636633" ]
[ "nonn" ]
35
0
5
[ "A000108", "A001796" ]
[ "M3116", "N1263" ]
N. J. A. Sloane
2024-10-31T15:10:25
oeisdata/seq/A001/A001796.seq
b632308f6acb7a041f9024cd4058e7ca
A001797
Coefficients of Legendre polynomials.
[ "2", "20", "110", "2600", "16150", "208012", "1376550", "74437200", "511755750", "7134913500", "50315410002", "1433226830360", "10292051290430", "148889972762300", "1083802983548950", "126935005433253024", "933787075442258310", "13799767368300523260" ]
[ "nonn" ]
20
0
5
null
[ "M2118", "N0836" ]
N. J. A. Sloane
2017-10-12T03:51:26
oeisdata/seq/A001/A001797.seq
bae8a570ad019588c8336dd14eb8c9ac
A001798
Coefficients of Legendre polynomials.
[ "2", "28", "182", "4760", "31654", "428260", "2941470", "163761840", "1152562950", "16381761396", "117402623338", "3390322778024", "24634522766126", "360043025043380", "2644479279859438", "312191499849352032", "2312918756095439814", "34398444513178377492" ]
[ "nonn", "changed" ]
27
0
5
[ "A001796", "A001798" ]
[ "M2149", "N0856" ]
N. J. A. Sloane
2025-04-24T08:50:24
oeisdata/seq/A001/A001798.seq
3cbeb0825b1575b6188e6f165c0d4c6a
A001799
Coefficients of Legendre polynomials.
[ "8", "72", "2160", "15504", "220248", "1564920", "89324640", "640807200", "9246847896", "67087213336", "1957095947664", "14342471475696", "211153052281080", "1560676296310488", "185256494416099008", "1379131680653181504", "20598677144877854232" ]
[ "nonn" ]
20
0
5
null
[ "M4557", "N1939" ]
N. J. A. Sloane
2017-10-12T03:51:20
oeisdata/seq/A001/A001799.seq
f18dba89c9071dbab4c11ff26287ae31
A001800
Coefficients of Legendre polynomials.
[ "1", "3", "30", "70", "315", "693", "12012", "25740", "109395", "230945", "1939938", "4056234", "16900975", "35102025", "1163381400", "2404321560", "9917826435", "20419054425", "167890003050", "344616322050", "1412926920405", "2893136075115", "47342226683700", "96742811049300", "395033145117975" ]
[ "nonn" ]
38
0
5
[ "A001790", "A001800", "A001801", "A001803", "A008316", "A100258" ]
[ "M3123", "N1266" ]
N. J. A. Sloane
2025-02-16T08:32:24
oeisdata/seq/A001/A001800.seq
0d8e2404bad6c34bf44f9228bf41f2e4