cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A093058 Numbers k such that numerator of Bernoulli(2k) is divisible by the square of 59, the second irregular prime.

Original entry on oeis.org

457, 1298, 2168, 3009, 3481, 3879, 4720, 5590, 6431, 6962, 7301, 8142, 9012, 9853, 10443, 10723, 11564, 12434, 13275, 13924, 14145, 14986, 15856, 16697, 17405, 17567, 18408
Offset: 1

Views

Author

Robert G. Wilson v, Feb 26 2004

Keywords

Crossrefs

Programs

  • Mathematica
    Select[ Range[ 9695], Mod[ Numerator[ BernoulliB[2# ]], 59^2] == 0 &]

Formula

If we omit multiples of 3481 and take first differences, it appears that we get a common difference of {841, 870} repeated.

Extensions

More terms from Eric W. Weisstein, Mar 19 2004

A093059 Numbers k such that the numerator of Bernoulli(2k) is divisible by the square of 67, the third irregular prime.

Original entry on oeis.org

1646, 1943, 3857, 4154, 4489, 6068, 6365, 8279, 8576, 8978, 10490, 10787, 12701, 12998, 13467, 14912, 15209, 17123, 17420, 17956
Offset: 1

Views

Author

Robert G. Wilson v, Feb 26 2004

Keywords

Crossrefs

Programs

  • Mathematica
    Select[ Range[ 9695], Mod[ Numerator[ BernoulliB[2# ]], 67^2] == 0 &]

Extensions

More terms from Eric W. Weisstein, Mar 19 2004

A281502 Numbers m such that the numerator of Bernoulli(2m) is divisible by 691.

Original entry on oeis.org

6, 100, 351, 445, 691, 696, 790, 1041, 1135, 1382, 1386, 1480, 1731, 1825, 2073, 2076, 2170, 2421, 2515, 2764, 2766, 2860, 3111, 3205, 3455, 3456, 3550, 3801, 3895, 4146, 4240, 4491, 4585, 4836, 4837, 4930, 5181, 5275, 5526, 5528, 5620, 5871, 5965
Offset: 1

Views

Author

Seiichi Manyama, Jan 23 2017

Keywords

Comments

6 + 345*k and 100 + 345*k are terms for k >= 0.

Examples

			Bernoulli(2*6) = -691/2730. So 6 is a term.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[4930],Mod[Numerator[BernoulliB[2#]],  691] == 0 &] (* Indranil Ghosh, Mar 11 2017 *)
  • PARI
    is(n) = Mod(numerator(bernfrac(2*n)), 691)==0 \\ Felix Fröhlich, Jan 23 2017
    
  • Python
    from itertools import count, islice
    from sympy import bernoulli
    def A281502gen(): return filter(lambda n:not bernoulli(2*n).p % 691,count(0))
    A281502_list = list(islice(A281502gen(),20)) # Chai Wah Wu, Dec 21 2021

Formula

a(n) = A119864(n)/2.

Extensions

a(12) - a(36) from Seiichi Manyama, Jan 24 2017
More terms from Indranil Ghosh, Mar 11 2017
Previous Showing 11-13 of 13 results.