A346464 a(n) = 6 * GaussBinomial(2*n, 2, 2) * Bernoulli(2*n, 1).

0, 1, -7, 93, -2159, 79205, -4243431, 313117357, -30459187423, 3777547352949, -581776592603735, 108932905225448381, -24370170371013413967, 6419958293615735090053, -1967044830254804722091719, 693575524342402846796188365, -278846808098157253796358662591

Offset: 0

Author

Peter Luschny, Jul 19 2021

Keywords

• sign

Crossrefs

Cf. A006095, A000367, A002445, A346463.

Programs

Maple

a := n -> `if`(n = 0, 0, -2*n*(4^n - 2)*(4^n - 1)*Zeta(1 - 2*n)):
seq(a(n), n = 0..16);

Mathematica

Table[6 QBinomial[2 n, 2, 2] BernoulliB[2 n, 1], {n, 0, 16}]

Formula

a(n) = -2*n*(4^n - 2)*(4^n - 1)*zeta(1 - 2*n) for n >= 1.