A318977 Expansion of e.g.f. Product_{k>=1} ((1 + x^k)/(1 - x^k))^(tau(k)/k), where tau is A000005.

1, 2, 8, 44, 292, 2296, 21472, 221168, 2554544, 32617952, 452957056, 6788855872, 110098330048, 1900192498304, 34971968379392, 683452436531456, 14097619892177152, 306168410773570048, 6998327049216231424, 167369475021548506112, 4187842602663179396096

Offset

0,2

Comments

Convolution of A318696 and A318695.

Links

Vaclav Kotesovec, Table of n, a(n) for n = 0..442

Mathematica

nmax = 20; CoefficientList[Series[Product[((1+x^k)/(1-x^k))^(DivisorSigma[0, k]/k), {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]!

Crossrefs

Cf. A318695, A318696, A318814, A318976.

Cf. A318975, A301555, A301554.

Sequence in context: A179489 A240165 A357832 * A111537 A051045 A112912

Adjacent sequences: A318974 A318975 A318976 * A318978 A318979 A318980

Keyword

nonn

Author

Vaclav Kotesovec, Sep 06 2018

Status

approved