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 A350721 #21 Feb 04 2022 10:03:03
%S A350721 1,1,31,4184,1495534,1110325474,1481505320078,3225820132807320,
%T A350721 10696978730747904696,51287741246274865567776,
%U A350721 341442095880058160040860592,3055472627228313328903357352784,35788671820468495762774011478900032
%N A350721 a(n) = Sum_{k=0..n} k! * k^(k+n) * Stirling1(n,k).
%H A350721 Seiichi Manyama, <a href="/A350721/b350721.txt">Table of n, a(n) for n = 0..161</a>
%F A350721 E.g.f.: Sum_{k>=0} (k * log(1 + k*x))^k.
%F A350721 a(n) ~ exp(-exp(-2)/2) * n! * n^(2*n). - _Vaclav Kotesovec_, Feb 04 2022
%t A350721 a[0] = 1; a[n_] := Sum[k! * k^(k+n) * StirlingS1[n, k], {k, 1, n}]; Array[a, 13, 0] (* _Amiram Eldar_, Feb 03 2022 *)
%o A350721 (PARI) a(n) = sum(k=0, n, k!*k^(k+n)*stirling(n, k, 1));
%o A350721 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k*log(1+k*x))^k)))
%Y A350721 Cf. A320083, A350719, A350720.
%Y A350721 Cf. A350722, A351135.
%K A350721 nonn
%O A350721 0,3
%A A350721 _Seiichi Manyama_, Feb 03 2022