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 A375796 #8 Aug 29 2024 11:24:43
%S A375796 1,1,2,6,36,240,1800,15960,164640,1905120,24343200,342619200,
%T A375796 5269017600,87749101440,1573083832320,30218175187200,619256461824000,
%U A375796 13483023576422400,310821905134540800,7563477205380096000,193736838233562624000,5210638309494858240000
%N A375796 Expansion of e.g.f. 1/(1 - (exp(x^3) - 1)/x^2).
%F A375796 a(n) = n! * Sum_{k=0..floor(n/3)} (n-3*k)! * Stirling2(n-2*k,n-3*k)/(n-2*k)!.
%o A375796 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-(exp(x^3)-1)/x^2)))
%o A375796 (PARI) a(n) = n!*sum(k=0, n\3, (n-3*k)!*stirling(n-2*k, n-3*k, 2)/(n-2*k)!);
%Y A375796 Cf. A000670, A375795.
%Y A375796 Cf. A357964.
%K A375796 nonn
%O A375796 0,3
%A A375796 _Seiichi Manyama_, Aug 29 2024