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 A356967 #10 Sep 06 2022 15:09:24
%S A356967 1,0,0,3,6,20,540,4284,35700,698760,10591560,155024100,3231336240,
%T A356967 68704908480,1451024062488,35843008924800,950925111973200,
%U A356967 25881184257364800,765471782499860160,24210772652940214320,797021694060934204800,27752674398657594805440
%N A356967 E.g.f. satisfies A(x) = 1/(1 - x * A(x))^(x^2/2 * A(x)).
%F A356967 a(n) = n! * Sum_{k=0..floor(n/3)} (n-k+1)^(k-1) * |Stirling1(n-2*k,k)|/(2^k * (n-2*k)!).
%o A356967 (PARI) a(n) = n!*sum(k=0, n\3, (n-k+1)^(k-1)*abs(stirling(n-2*k, k, 1))/(2^k*(n-2*k)!));
%Y A356967 Cf. A184949, A349556, A356968.
%Y A356967 Cf. A356752, A356962.
%K A356967 nonn
%O A356967 0,4
%A A356967 _Seiichi Manyama_, Sep 06 2022