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 A336949 #7 Aug 09 2020 03:32:54
%S A336949 1,2,14,195,4440,147745,6698448,394852577,29250137472,2652483234033,
%T A336949 288363456748800,36952298766628465,5504130616452258816,
%U A336949 941845623036360908489,183298110723156455921664,40221612394630225987208625,9876429434585097671993032704
%N A336949 a(n) = n! * [x^n] 1 / (exp(-n*x) - x).
%F A336949 a(n) = n! * Sum_{k=0..n} (n * (n-k+1))^k / k!.
%t A336949 Table[n! SeriesCoefficient[1/(Exp[-n x] - x), {x, 0, n}], {n, 0, 16}]
%t A336949 Join[{1}, Table[n! Sum[(n (n - k + 1))^k/k!, {k, 0, n}], {n, 1, 16}]]
%o A336949 (PARI) a(n)={n!*polcoef(1/(exp(-n*x + O(x*x^n)) - x), n)} \\ _Andrew Howroyd_, Aug 08 2020
%Y A336949 Cf. A063170, A072597, A235328, A336947, A336948.
%K A336949 nonn
%O A336949 0,2
%A A336949 _Ilya Gutkovskiy_, Aug 08 2020