A033473 - OEIS

A033473

Numerator of (2*n+1)!*8*Bernoulli(2*n,1/2).

8, -4, 28, -930, 96012, -24144750, 12602990070, -12203470904625, 20180112406353900, -53495387545025175750, 216267236072968468547250, -1280630367874799320798794375, 10743714652441927865738713818750, -124178158916511109662405449217796875

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

OFFSET

0,1

COMMENTS

As R. Israel remarks, the expression (2*n+1)!*8*Bernoulli(2*n,1/2) is no longer an integer for n = 15, 23, 27, 29, 30, 31, 39, 43, 45, 46, 47,... - M. F. Hasler, Feb 16 2014

Denominators are in A238015. See A238163 for the rounded values and A238164 for another maybe more interesting variant. - M. F. Hasler, Mar 01 2014

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..150

Index entries for sequences related to Bernoulli numbers.

MATHEMATICA

a[n_] := Numerator[ (2 n + 1)! 8 BernoulliB[2 n, 1/2]]; Array[a, 14, 0] (* Robert G. Wilson v, Feb 17 2014, edited by M. F. Hasler, Mar 01 2014 *)

Table[Numerator[(2 n + 1)! 8 BernoulliB[2 n, 1/2]], {n, 0, 20}] (* Vincenzo Librandi, Feb 18 2014 *)

PROG

(PARI) A033473 = n->numerator((2*n+1)!*8*subst(bernpol(2*n, x), x, 1/2)) \\ M. F. Hasler, Feb 16-18 2014

CROSSREFS

Cf. A238163, A238164.

Sequence in context: A143368 A160415 A160411 * A238163 A213773 A213178

Adjacent sequences: A033470 A033471 A033472 * A033474 A033475 A033476

KEYWORD

sign

AUTHOR

N. J. A. Sloane

EXTENSIONS

Definition changed by M. F. Hasler, Feb 16 2014

Further edits by M. F. Hasler, Mar 01 2014

STATUS

approved