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 A276527 #9 Nov 16 2016 04:10:25
%S A276527 1,-1,1,-3,5,-8,12,-21,37,-59,92,-153,256,-409,654,-1073,1754,-2824,
%T A276527 4552,-7394,12010,-19406,31337,-50782,82306,-133072,215152,-348346,
%U A276527 563939,-912217,1475604,-2388075,3864808,-6252750,10115987,-16369340,26488326,-42857128
%N A276527 Expansion of Product_{k>=1} 1 / (1 + x^k - x^(2*k)).
%H A276527 Vaclav Kotesovec, <a href="/A276527/b276527.txt">Table of n, a(n) for n = 0..1000</a>
%F A276527 a(n) ~ -p / (sqrt(5) * r^(n+1)), where r = -(sqrt(5)-1)/2 and p = Product_{n>1} 1/(1 + r^n - r^(2*n)) = 1.0964214808924344474065093...
%t A276527 nmax = 50; CoefficientList[Series[1/Product[1+x^k-x^(2*k), {k, 1, nmax}], {x, 0, nmax}], x]
%Y A276527 Cf. A003105, A162891.
%Y A276527 Cf. A000726, A109389, A263401.
%K A276527 sign
%O A276527 0,4
%A A276527 _Vaclav Kotesovec_, Nov 16 2016