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 A293849 #19 Apr 17 2022 22:07:44
%S A293849 1,1,5,67,1825,85661,6208861,643969495,90484635137,16538699920825,
%T A293849 3811890603086101,1081079416534448651,369888779067183276385,
%U A293849 150214056908992952336917,71424576855634502660684525,39304140073887410352909383071
%N A293849 Expansion of e.g.f.: exp(Sum_{n>=1} n^(n-1)*x^n).
%H A293849 Seiichi Manyama, <a href="/A293849/b293849.txt">Table of n, a(n) for n = 0..232</a>
%F A293849 E.g.f.: exp(Sum_{n>=1} n^(n-1)*x^n).
%F A293849 a(0) = 1 and a(n) = (n-1)! * Sum_{k=1..n} k^k*a(n-k)/(n-k)! for n > 0.
%F A293849 a(n) ~ n! * n^(n-1). - _Vaclav Kotesovec_, Oct 18 2017
%t A293849 nmax = 20; CoefficientList[Series[E^Sum[k^(k-1)*x^k, {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]! (* _Vaclav Kotesovec_, Oct 18 2017 *)
%o A293849 (PARI) {a(n) = n!*polcoeff(exp(sum(k=1, n, k^(k-1)*x^k)+x*O(x^n)), n)}
%Y A293849 Cf. A293848.
%K A293849 nonn
%O A293849 0,3
%A A293849 _Seiichi Manyama_, Oct 17 2017