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 A269155 #8 Feb 20 2016 09:07:53
%S A269155 1,-3,2,-5,17,-23,43,-87,178,-378,700,-1402,2837,-5651,11295,-22592,
%T A269155 45397,-90587,181187,-362566,724949,-1449986,2900068,-5801059,
%U A269155 11601675,-23204798,46409816,-92817126,185633688,-371270603,742544062,-1485079884,2970162411
%N A269155 Expansion of Product_{k>=1} (1 - k*x^k)/(1 + 2*x^k).
%H A269155 Vaclav Kotesovec, <a href="/A269155/b269155.txt">Table of n, a(n) for n = 0..3300</a>
%F A269155 a(n) ~ c * (-2)^n, where c = Product_{k>=1} ((-2)^k - k)/((-2)^k - 1) = 0.691544539061740396647761051109300225267201237557458470928297389967...
%t A269155 nmax = 50; CoefficientList[Series[Product[(1-k*x^k)/(1+2*x^k), {k, 1, nmax}], {x, 0, nmax}], x]
%Y A269155 Cf. A269144, A269153, A269154.
%K A269155 sign
%O A269155 0,2
%A A269155 _Vaclav Kotesovec_, Feb 20 2016