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 A371233 #8 Mar 16 2024 11:57:11
%S A371233 1,0,0,6,12,40,1620,16128,154560,3378240,67828320,1247843520,
%T A371233 28996704000,773215822080,20900234234880,609432997219200,
%U A371233 19677823129036800,674330219708221440,24327437969162280960,936555233579552563200,38250260222888409292800
%N A371233 E.g.f. satisfies A(x) = 1 - x^2*log(1 - x*A(x)^2).
%F A371233 a(n) = n! * Sum_{k=0..floor(n/3)} (2*n-4*k)! * |Stirling1(n-2*k,k)|/( (n-2*k)! * (2*n-5*k+1)! ).
%o A371233 (PARI) a(n) = n!*sum(k=0, n\3, (2*n-4*k)!*abs(stirling(n-2*k, k, 1))/((n-2*k)!*(2*n-5*k+1)!));
%Y A371233 Cf. A371234, A371235.
%Y A371233 Cf. A371118.
%K A371233 nonn
%O A371233 0,4
%A A371233 _Seiichi Manyama_, Mar 15 2024