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 A360990 #13 Mar 12 2023 10:18:23
%S A360990 1,1,7,-8,-827,2896,452179,-2511872,-560237303,4254259456,
%T A360990 1237434920191,-11907540107264,-4275828959720435,49800209789734912,
%U A360990 21288959122755516235,-290981680034059649024,-144324916601232035246831,2264121148389579474141184
%N A360990 E.g.f. satisfies A(x) = exp(x / A(-x)^3).
%F A360990 a(n) = Sum_{k=0..n} (-3*n + 3*k + 1)^(k-1) * (3*k)^(n-k) * binomial(n,k).
%p A360990 A360990 := proc(n)
%p A360990 add((-3*n+3*k+1)^(k-1)*(3*k)^(n-k)*binomial(n,k),k=0..n) ;
%p A360990 end proc:
%p A360990 seq(A360990(n),n=0..60) ; # _R. J. Mathar_, Mar 12 2023
%o A360990 (PARI) a(n) = sum(k=0, n, (-3*n+3*k+1)^(k-1)*(3*k)^(n-k)*binomial(n, k));
%Y A360990 Cf. A141369, A196198, A360987, A360988, A360989.
%K A360990 sign
%O A360990 0,3
%A A360990 _Seiichi Manyama_, Feb 27 2023