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 A375827 #9 Aug 31 2024 08:32:42
%S A375827 1,0,0,6,12,20,1110,10122,58856,1239912,23773770,303367790,5442263772,
%T A375827 135931189836,2868815413646,61708462976370,1696559552295120,
%U A375827 48121891688969552,1323641220801211026,40678367069424137814,1372011621943725532100
%N A375827 E.g.f. satisfies A(x) = exp(x^2 * (exp(x*A(x)) - 1)).
%F A375827 a(n) = n! * Sum_{k=0..floor(n/3)} (n-2*k+1)^(k-1) * Stirling2(n-2*k,k)/(n-2*k)!.
%o A375827 (PARI) a(n) = n!*sum(k=0, n\3, (n-2*k+1)^(k-1)*stirling(n-2*k, k, 2)/(n-2*k)!);
%Y A375827 Cf. A030019, A349560.
%Y A375827 Cf. A375826.
%K A375827 nonn
%O A375827 0,4
%A A375827 _Seiichi Manyama_, Aug 30 2024