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 A285990 #13 Apr 14 2019 11:55:09
%S A285990 1,-2,-14,-24,78,536,1236,-308,-12322,-45218,-73680,76144,872868,
%T A285990 2833904,4612952,-2467592,-42205746,-147191388,-285572658,-127256088,
%U A285990 1376616024,6138841704,14949184532,19201535108,-18287313476,-186761626394,-604980766280
%N A285990 Expansion of Product_{n>0} ((1-x^n)/(1+x^n))^(n^3) in powers of x.
%H A285990 Seiichi Manyama, <a href="/A285990/b285990.txt">Table of n, a(n) for n = 0..5987</a>
%F A285990 a(0) = 1, a(n) = -(2/n)*Sum_{k=1..n} A285989(k)*a(n-k) for n > 0.
%F A285990 G.f.: exp(Sum_{k>=1} (sigma_4(k) - sigma_4(2*k))*x^k/(8*k)). - _Ilya Gutkovskiy_, Apr 14 2019
%Y A285990 Product_{n>0} ((1-x^n)/(1+x^n))^(n^m): A002448 (m=0), A285675 (m=1), A285988 (m=2), this sequence (m=3), A285991 (m=4).
%Y A285990 Cf. A206623, A285989.
%K A285990 sign
%O A285990 0,2
%A A285990 _Seiichi Manyama_, Apr 30 2017