This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A289350 #14 Jul 08 2017 07:37:02 %S A289350 1,-22,-115,-350,-940,-2124,-4615,-9130,-17575,-32100,-57239,-98512, %T A289350 -166595,-274350,-445055,-708124,-1112002,-1719410,-2629450,-3970230, %U A289350 -5937238,-8785502,-12889630,-18741250,-27045445,-38724088,-55074057,-77791320,-109215025 %N A289350 Coefficients in expansion of E_2/Product_{k>=1} (1-q^k)^2. %F A289350 G.f.: Product_{k>=1} (1-q^k)^(A288995(k)/12). %F A289350 a(n) ~ -3^(1/4) * exp(2*Pi*sqrt(n/3)) / n^(1/4). - _Vaclav Kotesovec_, Jul 08 2017 %t A289350 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 A289350 E_2^(m/2)/Product_{k>=1} (1-q^k)^m: A289344 (m=1), this sequence (m=2), A289062 (m=24). %Y A289350 Cf. A006352 (E_2), A066186, A288995. %K A289350 sign %O A289350 0,2 %A A289350 _Seiichi Manyama_, Jul 03 2017