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%I #14 Jul 08 2017 07:37:02
%S 1,-22,-115,-350,-940,-2124,-4615,-9130,-17575,-32100,-57239,-98512,
%T -166595,-274350,-445055,-708124,-1112002,-1719410,-2629450,-3970230,
%U -5937238,-8785502,-12889630,-18741250,-27045445,-38724088,-55074057,-77791320,-109215025
%N Coefficients in expansion of E_2/Product_{k>=1} (1-q^k)^2.
%F G.f.: Product_{k>=1} (1-q^k)^(A288995(k)/12).
%F a(n) ~ -3^(1/4) * exp(2*Pi*sqrt(n/3)) / n^(1/4). - _Vaclav Kotesovec_, Jul 08 2017
%t nmax = 50; CoefficientList[Series[(1 - 24*Sum[DivisorSigma[1, k]*x^k, {k, 1, nmax}]) / Product[(1 - x^k)^2, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Jul 08 2017 *)
%Y E_2^(m/2)/Product_{k>=1} (1-q^k)^m: A289344 (m=1), this sequence (m=2), A289062 (m=24).
%Y Cf. A006352 (E_2), A066186, A288995.
%K sign
%O 0,2
%A _Seiichi Manyama_, Jul 03 2017
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