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%I #12 Oct 26 2018 16:53:54
%S 1,1,65,795,6971,69317,690756,6316950,55729130,484275457,4111328940,
%T 34029153900,275901508917,2197552381491,17207716281240,
%U 132575879110175,1006214596929014,7531171360277228,55632520744009711,405876769498808480,2926507055330036936
%N Expansion of Product_{k>=1} (1 + x^k)^(sigma_6(k)).
%H Seiichi Manyama, <a href="/A301550/b301550.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) ~ exp(2^(5/2) * Pi * (127*Zeta(7)/15)^(1/8) * n^(7/8)/7 - Pi * (5/(127*Zeta(7)))^(1/8) * n^(1/8) / (504 * sqrt(2) * 3^(7/8))) * (127*Zeta(7)/15)^(1/16) / (2^(9/4) * n^(9/16)).
%F G.f.: exp(Sum_{k>=1} sigma_7(k)*x^k/(k*(1 - x^(2*k)))). - _Ilya Gutkovskiy_, Oct 26 2018
%t nmax = 30; CoefficientList[Series[Product[(1+x^k)^DivisorSigma[6, k], {k, 1, nmax}], {x, 0, nmax}], x]
%Y Cf. A013954, A107742, A301544.
%K nonn
%O 0,3
%A _Vaclav Kotesovec_, Mar 23 2018
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