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 A291646 #5 Feb 16 2025 08:33:50
%S A291646 1,0,-1,-1,2,6,-1,-29,-32,108,311,-185,-1991,-1590,9468,22163,-26645,
%T A291646 -170511,-70359,955734,1755790,-3561052,-16020532,309754,102695477,
%U A291646 141637053,-463468990,-1567907433,806541136,11367276801,10768399120,-59447130815,-155142592628,172852194214,1273466836673
%N A291646 Expansion of the series reversion of -1 + Product_{k>=1} (1 + x^(2*k-1)).
%C A291646 Reversion of g.f. (with constant term omitted) for A000700.
%H A291646 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%H A291646 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SeriesReversion.html">Series Reversion</a>
%H A291646 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A291646 G.f. A(x) satisfies: -1 + Product_{k>=1} (1 + A(x)^(2*k-1)) = x.
%t A291646 nmax = 35; Rest[CoefficientList[InverseSeries[Series[-1 + Product[1 + x^(2 k - 1), {k, 1, nmax}], {x, 0, nmax}], x], x]]
%t A291646 nmax = 35; Rest[CoefficientList[InverseSeries[Series[-1 + QPochhammer[x^2]^2/(QPochhammer[x] QPochhammer[x^4]), {x, 0, nmax}], x], x]]
%Y A291646 Cf. A000700, A007312, A050393, A291489.
%K A291646 sign
%O A291646 1,5
%A A291646 _Ilya Gutkovskiy_, Aug 28 2017