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A067778 Numbers n such that GCD(n,numerator(B(2n)) is not squarefree where B(2n) are the Bernoulli numbers. 3
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 * A067893 A067794 A068874

Adjacent sequences:  A067775 A067776 A067777 * A067779 A067780 A067781

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 06 2002

EXTENSIONS

More terms from Robert G. Wilson v, Aug 28 2004

'Needs["NumberTheory`"]' (no longer needed) removed from Mathematica code by Jean-Fran├žois Alcover, Dec 04 2013

STATUS

approved

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Last modified March 25 01:17 EDT 2019. Contains 321450 sequences. (Running on oeis4.)