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 A377532 #9 Oct 31 2024 13:24:57
%S A377532 1,0,6,18,180,1500,15930,191646,2580648,38683224,636068430,
%T A377532 11392350090,220658360076,4594593295188,102333126352002,
%U A377532 2427278515815510,61079333377870800,1625065147997303856,45576552142354413078,1343802083242003570818,41552482139458105525620
%N A377532 Expansion of e.g.f. 1/(1 - x^2 * exp(x))^3.
%F A377532 a(n) = n! * Sum_{k=0..floor(n/2)} k^(n-2*k) * binomial(k+2,2)/(n-2*k)!.
%F A377532 a(n) ~ n! * n^2 / ((1 + LambertW(1/2))^3 * 2^(n+4) * LambertW(1/2)^n). - _Vaclav Kotesovec_, Oct 31 2024
%o A377532 (PARI) a(n) = n!*sum(k=0, n\2, k^(n-2*k)*binomial(k+2, 2)/(n-2*k)!);
%Y A377532 Cf. A358080, A377531.
%K A377532 nonn,easy
%O A377532 0,3
%A A377532 _Seiichi Manyama_, Oct 31 2024