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 A375811 #14 Sep 01 2024 10:49:37
%S A375811 1,3,12,69,504,4380,44280,509670,6572160,93813552,1467910080,
%T A375811 24976440720,459045195840,9061616266560,191187467190720,
%U A375811 4293103436622000,102216550583347200,2572022267758944000,68195046359419499520,1900236334204732043520
%N A375811 Expansion of e.g.f. 1/(1 - (exp(x^2) - 1)/x)^3.
%F A375811 E.g.f.: B(x)^3, where B(x) is the e.g.f. of A375795.
%F A375811 a(n) = (n!/2) * Sum_{k=0..floor(n/2)} (n-2*k+2)! * Stirling2(n-k,n-2*k)/(n-k)!.
%o A375811 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1-(exp(x^2)-1)/x)^3))
%o A375811 (PARI) a(n) = n!*sum(k=0, n\2, (n-2*k+2)!*stirling(n-k, n-2*k, 2)/(n-k)!)/2;
%Y A375811 Cf. A375795, A375810.
%Y A375811 Cf. A375665.
%K A375811 nonn
%O A375811 0,2
%A A375811 _Seiichi Manyama_, Aug 29 2024