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%I #6 May 26 2018 18:24:06
%S 0,0,1,6,21,60,148,334,702,1396,2660,4880,8687,15044,25470,42212,
%T 68724,110000,173522,269930,414812,630032,947007,1409266,2078335,
%U 3038540,4407334,6344176,9068278,12874676,18164356,25472626,35519617,49259628,67964527,93308202
%N G.f.: (Sum_{k>=1} x^k/(1-x^k) * Product_{k>=1} 1/(1-x^k) )^2.
%C Self-convolution of A006128.
%H Vaclav Kotesovec, <a href="/A305120/b305120.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) ~ 3^(1/4)*(2*gamma+log(3*n/Pi^2))^2 * exp(2*Pi*sqrt(n/3)) / (16*Pi^2*n^(1/4)), where gamma is the Euler-Mascheroni constant A001620.
%t nmax = 40; CoefficientList[Series[(Sum[x^k/(1-x^k), {k, 1, nmax}] * Product[1/(1-x^k), {k, 1, nmax}])^2, {x, 0, nmax}], x]
%Y Cf. A006128, A000712, A305119.
%K nonn
%O 0,4
%A _Vaclav Kotesovec_, May 26 2018