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Expansion of Product_{1 <= i < j} 1/(1 - x^(i*j)).
3

%I #15 Nov 02 2018 12:11:38

%S 1,0,1,1,2,2,5,4,9,9,16,17,31,31,52,59,89,101,154,172,254,294,412,483,

%T 675,782,1070,1265,1686,1996,2647,3121,4086,4854,6252,7442,9534,11306,

%U 14360,17092,21489,25566,31989,37981,47224,56123,69283,82290,101185,119930,146768

%N Expansion of Product_{1 <= i < j} 1/(1 - x^(i*j)).

%H Seiichi Manyama, <a href="/A321285/b321285.txt">Table of n, a(n) for n = 0..10000</a>

%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>

%F Euler transform of A056924.

%F G.f.: Product_{k>0} 1/(1 - x^k)^A056924(k).

%t nmax = 50; CoefficientList[Series[Product[1/(1 - x^k)^Floor[DivisorSigma[0, k]/2], {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Nov 02 2018 *)

%Y Cf. A056924, A182269, A321286.

%K nonn

%O 0,5

%A _Seiichi Manyama_, Nov 02 2018