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 A356968 #9 Sep 06 2022 14:26:48
%S A356968 1,0,0,0,4,10,40,210,4144,40320,409800,4527600,72552480,1170449280,
%T A356968 19489513680,338983444800,6672681818880,141166715289600,
%U A356968 3149324442700800,73497460049395200,1825098639493104000,47984287767342796800,1326460667797094860800
%N A356968 E.g.f. satisfies A(x) = 1/(1 - x * A(x))^(x^3/6 * A(x)).
%F A356968 a(n) = n! * Sum_{k=0..floor(n/4)} (n-2*k+1)^(k-1) * |Stirling1(n-3*k,k)|/(6^k * (n-3*k)!).
%o A356968 (PARI) a(n) = n!*sum(k=0, n\4, (n-2*k+1)^(k-1)*abs(stirling(n-3*k, k, 1))/(6^k*(n-3*k)!));
%Y A356968 Cf. A184949, A349556, A356967.
%Y A356968 Cf. A356753, A356963.
%K A356968 nonn
%O A356968 0,5
%A A356968 _Seiichi Manyama_, Sep 06 2022