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%I #6 Sep 01 2018 03:55:21
%S 1,2,8,20,56,128,316,684,1532,3192,6704,13436,26984,52352,101316,
%T 191320,359334,662292,1213360,2189380,3925432,6951592,12231332,
%U 21298452,36856840,63211164,107765896,182295468,306625208,512190992,851011960,1405199028,2308629300,3771593392
%N Expansion of Product_{i>=1, j>=1, k>=1} (1 + x^(i*j*k))/(1 - x^(i*j*k)).
%C Convolution of the sequences A174465 and A280473.
%H Vaclav Kotesovec, <a href="/A305050/b305050.txt">Table of n, a(n) for n = 0..10000</a>
%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F G.f.: Product_{k>=1} ((1 + x^k)/(1 - x^k))^A007425(k).
%t nmax = 33; CoefficientList[Series[Product[(1 + x^(i j k))/(1 - x^(i j k)), {i, 1, nmax}, {j, 1, nmax/i}, {k, 1, nmax/i/j}], {x, 0, nmax}], x]
%t nmax = 33; CoefficientList[Series[Product[((1 + x^k)/(1 - x^k))^Sum[DivisorSigma[0, d], {d, Divisors[k]}], {k, 1, nmax}], {x, 0, nmax}], x]
%Y Cf. A007425, A174465, A280473, A301554.
%K nonn
%O 0,2
%A _Ilya Gutkovskiy_, May 24 2018