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 A354889 #19 Jun 11 2022 07:51:54
%S A354889 1,4,15,112,745,10296,122689,2285312,43953921,1026157600,25977341401,
%T A354889 751135431168,23304312143281,795924137531264,29203006015310625,
%U A354889 1154107395053387776,48661547563094964481,2186762596692631699968,104127471943011650364841
%N A354889 a(n) = n! * Sum_{d|n} d^(d-1) / d!.
%H A354889 Seiichi Manyama, <a href="/A354889/b354889.txt">Table of n, a(n) for n = 1..387</a>
%F A354889 E.g.f.: Sum_{k>0} k^(k-1) * x^k/(k! * (1 - x^k)).
%F A354889 If p is prime, a(p) = p^(p-1) + p!.
%t A354889 a[n_] := n! * DivisorSum[n, #^(# - 1)/#! &]; Array[a, 19] (* _Amiram Eldar_, Jun 10 2022 *)
%o A354889 (PARI) a(n) = n!*sumdiv(n, d, d^(d-1)/d!);
%o A354889 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=1, N, k^(k-1)*x^k/(k!*(1-x^k)))))
%Y A354889 Cf. A262843, A327578, A354845, A354888.
%K A354889 nonn
%O A354889 1,2
%A A354889 _Seiichi Manyama_, Jun 10 2022