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Expansion of e.g.f. Product_{k>=1} ((1 + x^k)/(1 - x^k))^(tau(k)/k), where tau is A000005.
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%I #9 Feb 28 2024 10:49:08

%S 1,2,8,44,292,2296,21472,221168,2554544,32617952,452957056,6788855872,

%T 110098330048,1900192498304,34971968379392,683452436531456,

%U 14097619892177152,306168410773570048,6998327049216231424,167369475021548506112,4187842602663179396096

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

%C Convolution of A318696 and A318695.

%H Vaclav Kotesovec, <a href="/A318977/b318977.txt">Table of n, a(n) for n = 0..442</a>

%t 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]!

%Y Cf. A318695, A318696, A318814, A318976.

%Y Cf. A318975, A301555, A301554.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Sep 06 2018