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 A375833 #6 Aug 31 2024 08:32:51
%S A375833 1,0,0,6,0,60,1440,840,100800,1829520,6350400,419459040,7125148800,
%T A375833 72657224640,3691516308480,66691652227200,1362335156582400,
%U A375833 60600254383468800,1285478183493504000,40463468995171622400,1701073478756171520000
%N A375833 E.g.f. satisfies A(x) = 1/(1 - x*(exp(x^2*A(x)) - 1)).
%F A375833 a(n) = n! * Sum_{k=0..floor(n/2)} (n-k)! * Stirling2(k,n-2*k)/( k! * (k+1)! ).
%o A375833 (PARI) a(n) = n!*sum(k=0, n\2, (n-k)!*stirling(k, n-2*k, 2)/(k!*(k+1)!));
%Y A375833 Cf. A371304.
%K A375833 nonn
%O A375833 0,4
%A A375833 _Seiichi Manyama_, Aug 30 2024