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 A328007 #9 Oct 02 2019 05:45:13
%S A328007 1,0,1,2,15,84,705,6222,65779,765608,9999333,143009250,2235857943,
%T A328007 37833382716,689729792713,13469761663862,280613761282875,
%U A328007 6211105772020560,145566258957724845,3601055676894146442,93772841089130278495,2563969299245947753700,73443322391840827563921
%N A328007 Expansion of e.g.f. 1 / (2 - exp(-x) / (1 - x)).
%F A328007 a(0) = 1; a(n) = Sum_{k=1..n} binomial(n,k) * A000166(k) * a(n-k).
%F A328007 a(n) ~ n! * (-LambertW(-exp(-1)/2) / (2*(1 + LambertW(-exp(-1)/2))^(n+2))). - _Vaclav Kotesovec_, Oct 02 2019
%t A328007 nmax = 22; CoefficientList[Series[1/(2 - Exp[-x]/(1 - x)), {x, 0, nmax}], x] Range[0, nmax]!
%t A328007 a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k] Subfactorial[k] a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 22}]
%o A328007 (PARI) my(x='x+O('x^25)); Vec(serlaplace(1 / (2 - exp(-x) / (1 - x)))) \\ _Michel Marcus_, Oct 02 2019
%Y A328007 Cf. A000166, A002866, A302557, A321989, A328008.
%K A328007 nonn
%O A328007 0,4
%A A328007 _Ilya Gutkovskiy_, Oct 01 2019