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 A360989 #17 Mar 18 2023 05:00:15
%S A360989 1,1,5,1,-231,81,55453,-40431,-30313231,33477985,29630916981,
%T A360989 -43713004191,-45378051616631,83666428734513,100216964952070541,
%U A360989 -221570666935625999,-301515678925659598623,777062158771833364929,1185517627245415533666277
%N A360989 E.g.f. satisfies A(x) = exp(x / A(-x)^2).
%H A360989 Winston de Greef, <a href="/A360989/b360989.txt">Table of n, a(n) for n = 0..366</a>
%F A360989 a(n) = Sum_{k=0..n} (-2*n + 2*k + 1)^(k-1) * (2*k)^(n-k) * binomial(n,k).
%o A360989 (PARI) a(n) = sum(k=0, n, (-2*n+2*k+1)^(k-1)*(2*k)^(n-k)*binomial(n, k));
%Y A360989 Cf. A141369, A196198, A360987, A360988, A360990.
%K A360989 sign
%O A360989 0,3
%A A360989 _Seiichi Manyama_, Feb 27 2023