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 A261610 #5 Aug 26 2015 12:19:31
%S A261610 1,2,2,2,4,6,6,8,12,14,16,22,28,32,40,50,58,70,86,100,118,144,168,194,
%T A261610 232,272,312,366,428,490,568,660,754,866,1000,1140,1300,1492,1696,
%U A261610 1924,2196,2490,2812,3192,3610,4062,4588,5174,5806,6530,7342,8218,9208
%N A261610 Expansion of Product_{k>=0} (1 + x^(3*k+1))/(1 - x^(3*k+1)).
%F A261610 a(n) ~ exp(Pi*sqrt(n/3)) * Gamma(1/3) / (2^(5/3) * 3^(1/3) * Pi^(2/3) * n^(2/3)).
%t A261610 nmax = 60; CoefficientList[Series[Product[(1 + x^(3*k+1))/(1 - x^(3*k+1)), {k, 0, nmax}], {x, 0, nmax}], x]
%Y A261610 Cf. A015128, A080054, A261611.
%K A261610 nonn
%O A261610 0,2
%A A261610 _Vaclav Kotesovec_, Aug 26 2015