The On-Line Encyclopedia of Integer Sequences (OEIS)

A067778 revision #25

A067778

Numbers n such that gcd(n, numerator(B(2n))) is not squarefree where B(2n) are the Bernoulli numbers.

25, 49, 75, 98, 121, 125, 169, 175, 196, 225, 242, 245, 275, 289, 325, 338, 343, 361, 363, 375, 392, 425, 475, 484, 490, 507, 525, 529, 539, 575, 578, 625, 637, 675, 676, 686, 722, 725, 726, 775, 784, 825, 833, 841, 845, 847, 867, 875, 925, 931, 961, 968

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

All members so far are themselves not squarefree. - Robert G. Wilson v, Aug 28 2004

LINKS

Table of n, a(n) for n=1..52.

MATHEMATICA

Select[ Range[1000], !SquareFreeQ[ GCD[ #, Numerator[ BernoulliB[2# ]] ]] &] (* Robert G. Wilson v, Aug 28 2004 *)

CROSSREFS

Cf. A097704.

Sequence in context: A020196 A020294 A103214 * A350061 A067893 A067794