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 A375813 #13 Sep 01 2024 10:13:52
%S A375813 1,3,12,60,396,3240,30960,335160,4072320,54976320,815119200,
%T A375813 13152585600,229441766400,4303027048320,86318858545920,
%U A375813 1843929831744000,41786821607731200,1001231951502182400,25288602517469491200,671488122628741017600
%N A375813 Expansion of e.g.f. 1/(1 - (exp(x^3) - 1)/x^2)^3.
%F A375813 E.g.f.: B(x)^3, where B(x) is the e.g.f. of A375796.
%F A375813 a(n) = (n!/2) * Sum_{k=0..floor(n/3)} (n-3*k+2)! * Stirling2(n-2*k,n-3*k)/(n-2*k)!.
%o A375813 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1-(exp(x^3)-1)/x^2)^3))
%o A375813 (PARI) a(n) = n!*sum(k=0, n\3, (n-3*k+2)!*stirling(n-2*k, n-3*k, 2)/(n-2*k)!)/2;
%Y A375813 Cf. A375796, A375812.
%Y A375813 Cf. A375809.
%K A375813 nonn
%O A375813 0,2
%A A375813 _Seiichi Manyama_, Aug 29 2024