A122273 a(n) is the smallest prime p such that p^4 divides the numerator of the Bernoulli number B(A122272(n)).

5, 5, 7, 5, 5, 7

Offset

1,1

Comments

The numbers m in A122272 are such that the numerator of the Bernoulli number B(m) is divisible by p^4, where p is a prime. For m = 6250, we have that the numerator of B(6250) is divisible by 5^5.

Links

Table of n, a(n) for n=1..6.

The Bernoulli Number Page, Table of factors of the numerators of Bernoulli numbers Bn in the range n = 2..10000, 2018.

S. S. Wagstaff, Jr, Prime factors of the absolute values of Bernoulli numerators, 2018.

Crossrefs

Cf. A000367, A090987, A090997, A122270, A122271, A122272.

Sequence in context: A234473 A011500 A003103 * A052247 A088201 A352353

Adjacent sequences: A122270 A122271 A122272 * A122274 A122275 A122276

Keyword

nonn,more

Author

Alexander Adamchuk, Aug 28 2006

Extensions

Various sections edited by Petros Hadjicostas, May 12 2020

Status

approved