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.

A295587 Numbers k such that Bernoulli number B_{k} has denominator 13530.

Original entry on oeis.org

40, 6680, 7880, 8920, 9080, 10280, 12520, 12680, 14120, 15320, 15560, 18280, 20840, 21640, 22760, 23480, 25720, 26440, 28040, 30040, 30280, 31880, 33080, 33560, 34520, 35240, 35480, 36280, 38680, 39640, 42040, 43880, 44360, 46120, 46520, 46840, 47240, 47720, 48520
Offset: 1

Views

Author

Paolo P. Lava, Nov 24 2017

Keywords

Comments

13530 = 2*3*5*11*41.
All terms are multiples of a(1) = 40.
For these numbers numerator(B_{k}) mod denominator(B_{k}) = 11519.

Examples

			Bernoulli B_{40} is -261082718496449122051/13530, hence 40 is in the sequence.
		

Crossrefs

Programs

  • Maple
    with(numtheory): P:=proc(q, h) local n;  for n from 2 by 2 to q do
    if denom(bernoulli(n))=h then print(n); fi; od; end: P(10^6,13530);
    # Alternative: # according to Robert Israel code in A282773
    with(numtheory): filter:= n ->
    select(isprime, map(`+`, divisors(n), 1)) = {2, 3, 5, 11, 41}:
    select(filter, [seq(i, i=1..10^5)]);
  • Mathematica
    Select[Range[50000],Denominator[BernoulliB[#]]==13530&] (* Harvey P. Dale, Jul 29 2025 *)