A160110 Numerators of |Bernoulli(n)*Gould(n)| for even n, (Gould A001316).

1, 1, 1, 2, 1, 10, 1382, 28, 3617, 87734, 349222, 3418052, 472728182, 34212412, 94997844116, 68926730208040, 7709321041217, 5155375716734, 52630543106106954746, 11719975655366236, 522165436992898244102

Offset

0,4

Comments

A001897 give the denominators of |Bernoulli(n)*Gould(n)| for even n, also the denominators of the cosecant numbers.

Links

G. C. Greubel, Table of n, a(n) for n = 0..314

Maple

b := n -> bernoulli(n)*2^add(i, i=convert(n, base, 2));
a := n -> numer(abs(b(2*n)));

Mathematica

G[n_] := Sum[Mod[Binomial[n, k], 2], {k, 0, n}]; (* A001316 *) Table[Abs[BernoulliB[n]*G[n]], {n, 0, 20}][[1 ;; -1 ;; 2]]//Numerator (* G. C. Greubel, Sep 25 2018 *)

Crossrefs

Cf. A001897.

Sequence in context: A239070 A271042 A098290 * A258055 A339306 A139393

Adjacent sequences: A160107 A160108 A160109 * A160111 A160112 A160113

Keyword

frac,nonn

Author

Peter Luschny, May 02 2009

Status

approved