A046753 Prime factors of |numerator(B(2n))| which are >= 2n+3.

691, 3617, 43867, 283, 617, 131, 593, 103, 2294797, 657931, 9349, 362903, 1721, 1001259881, 37, 683, 305065927, 151628697551, 26315271553053477373, 154210205991661, 137616929, 1897170067619, 1520097643918070802691, 59

Offset: 1

Author

Bill Gosper

Keywords

• nonn

Comments

See A189683 for pairs (p,2n) for the primes p in this sequence.

Links

• Robert G. Wilson v, Table of n, a(n) for n = 1..154 (first 66 terms from T. D. Noe)
• Hisanori Mishima, WIFC (World Integer Factorization Center)

Crossrefs

Cf. A000367, A000928, A189683, A189684, A189685.

Programs

Macsyma

for n do for p in map('first,factor_number(abs(num(bern(2*n))))) do if p>=2*n+3 then (?prin1(p),?prin1('?\-));

Mathematica

Flatten[Table[Select[First /@ FactorInteger[Abs[Numerator[BernoulliB[n]]]], # >= n+3 &], {n, 2, 70, 2}]] (* T. D. Noe, Apr 25 2011 *)

Extensions

Definition modified by Jonathan Sondow, Apr 27 2011