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 A351280 #15 Feb 06 2022 11:02:56
%S A351280 1,1,7,140,5254,318854,28455182,3506576856,570360248856,
%T A351280 118356589567440,30512901324706608,9566812017770347152,
%U A351280 3584662956711860108352,1581905384865801328253712,812047187127758913474118032,479763784808095613489811245568
%N A351280 a(n) = Sum_{k=0..n} k! * k^k * Stirling1(n,k).
%F A351280 E.g.f.: Sum_{k>=0} (k * log(1+x))^k.
%F A351280 a(n) ~ exp(-exp(-1)/2) * n! * n^n. - _Vaclav Kotesovec_, Feb 06 2022
%t A351280 a[0] = 1; a[n_] := Sum[k! * k^k * StirlingS1[n, k], {k, 1, n}]; Array[a, 16, 0] (* _Amiram Eldar_, Feb 06 2022 *)
%o A351280 (PARI) a(n) = sum(k=0, n, k!*k^k*stirling(n, k, 1));
%o A351280 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k*log(1+x))^k)))
%Y A351280 Cf. A006252, A305819, A320083, A350721, A350725, A351281.
%K A351280 nonn
%O A351280 0,3
%A A351280 _Seiichi Manyama_, Feb 06 2022