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 A377964 #10 Nov 13 2024 06:47:25
%S A377964 1,2,9,58,389,3186,29437,294554,3233673,38350594,484794641,6522118362,
%T A377964 92857444429,1390937221298,21858658599429,359271578140666,
%U A377964 6156249977141777,109722278546645634,2029772196329985433,38893956306343711994,770622936760496106261,15763542538016019828082
%N A377964 Expansion of e.g.f. (1+x) * exp(x*(1+x)^3).
%F A377964 a(n) = n! * Sum_{k=0..n} binomial(3*k+1,n-k) / k!.
%o A377964 (PARI) a(n, s=1, t=3) = n!*sum(k=0, n, binomial(t*k+s, n-k)/k!);
%Y A377964 Cf. A018191, A377963.
%Y A377964 Cf. A361279, A377966, A377967.
%K A377964 nonn,easy
%O A377964 0,2
%A A377964 _Seiichi Manyama_, Nov 12 2024