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 A377681 #8 Nov 04 2024 09:15:12
%S A377681 1,0,8,12,160,740,5424,37828,262784,1868868,13200880,89816804,
%T A377681 581630592,3586158628,21162503600,120273982980,662169758464,
%U A377681 3549104142980,18595278255600,95559668680612,482965743234560,2405973280450404,11835507260403376,57577781030368196
%N A377681 Expansion of e.g.f. (1 + x * (exp(x) - 1))^4.
%F A377681 a(n) = n! * Sum_{k=0..floor(n/2)} k! * binomial(4,k) * Stirling2(n-k,k)/(n-k)!.
%o A377681 (PARI) a(n) = n!*sum(k=0, n\2, k!*binomial(4, k)*stirling(n-k, k, 2)/(n-k)!);
%Y A377681 Cf. A377646, A377680.
%K A377681 nonn,easy
%O A377681 0,3
%A A377681 _Seiichi Manyama_, Nov 04 2024