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 A365286 #7 Aug 31 2023 08:16:47
%S A365286 1,1,2,6,48,600,7920,108360,1693440,32114880,715478400,17616614400,
%T A365286 467505561600,13438170345600,421361740800000,14345678194848000,
%U A365286 524464774215782400,20420391682852761600,844038690729589555200,36981569420732192256000
%N A365286 E.g.f. satisfies A(x) = 1 + x*A(x)*exp(x^3*A(x)^2).
%F A365286 a(n) = n! * Sum_{k=0..floor(n/3)} (n-3*k)^k * binomial(n-k+1,n-3*k)/( (n-k+1)*k! ).
%o A365286 (PARI) a(n) = n!*sum(k=0, n\3, (n-3*k)^k*binomial(n-k+1, n-3*k)/((n-k+1)*k!));
%Y A365286 Cf. A358065, A365285, A365287.
%K A365286 nonn
%O A365286 0,3
%A A365286 _Seiichi Manyama_, Aug 31 2023