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 A375634 #8 Aug 22 2024 09:17:22
%S A375634 1,1,2,12,52,280,2160,16870,150080,1557360,17491600,215908000,
%T A375634 2923905600,42734091400,672515043200,11347480544400,204142655516800,
%U A375634 3902009862150400,78976503077472000,1687212801048174400,37941749192547200000
%N A375634 Expansion of e.g.f. exp(x^3) / (1 - x * exp(x^3/6)).
%F A375634 a(n) = n! * Sum_{k=0..floor(n/3)} ((n-3*k+6)/6)^k/k!.
%o A375634 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x^3)/(1-x*exp(x^3/6))))
%o A375634 (PARI) a(n) = n!*sum(k=0, n\3, ((n-3*k+6)/6)^k/k!);
%Y A375634 Cf. A358265, A375607, A375633.
%K A375634 nonn
%O A375634 0,3
%A A375634 _Seiichi Manyama_, Aug 22 2024