A081739 a(n) = (-1/2^n)*(A000367(2^n)+1).

0, 0, 452, 481832565076, 3336994692120829058949545155598207748188, 4183667308477313795108662587270037418426429056133620947343416969739965511482242658521291610836247844507748569589344

Offset: 1

Author

Benoit Cloitre, Apr 06 2003

Keywords

• nonn

Crossrefs

Cf. A000367, A076547.

Programs

Mathematica

a[n_] := -(Numerator[BernoulliB[2^(n+1)]] + 1)/2^n; Array[a, 6] (* Amiram Eldar, May 03 2025 *)

PARI

a(n) = -(numerator(bernfrac(1 << (n+1))) + 1) >> n; \\ Amiram Eldar, May 03 2025

Formula

a(n) = A076547(n)-1 (Conjecture). - R. J. Mathar, Apr 22 2007