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 A305255 #4 May 29 2018 00:47:34
%S A305255 1,-1,-1,-4,-3,14,240,1686,9479,36761,3412,-1951731,-27296124,
%T A305255 -268495319,-2093667873,-11586874946,-3788945531,1127535019748,
%U A305255 21900095232973,297591401221473,3270627818325128,28116733997044842,129815302615081267,-1568168714539146596,-59839621829784309343
%N A305255 a(n) = [x^n] exp(Sum_{k>=1} (-1)^k*x^k/(k*(1 - x^k)^n)).
%H A305255 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F A305255 a(n) = [x^n] Product_{k>=1} 1/(1 + x^k)^binomial(n+k-2,n-1).
%t A305255 Table[SeriesCoefficient[Exp[Sum[(-1)^k x^k/(k (1 - x^k)^n), {k, 1, n}]], {x, 0, n}], {n, 0, 24}]
%t A305255 Table[SeriesCoefficient[Product[1/(1 + x^k)^Binomial[n + k - 2, n - 1], {k, 1, n}], {x, 0, n}], {n, 0, 24}]
%Y A305255 Cf. A255528, A293554, A294846, A305205, A305206.
%K A305255 sign
%O A305255 0,4
%A A305255 _Ilya Gutkovskiy_, May 28 2018