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 A328488 #7 Oct 17 2019 18:48:55
%S A328488 1,1,5,34,307,3456,46659,734882,13227995,267871036,6027206803,
%T A328488 149176155030,4027831914099,117816299188472,3711283196035523,
%U A328488 125258162280991858,4509378597919760779,172486973301491042964,6985853719202139488211,298650859698906574479278
%N A328488 Expansion of e.g.f. 1 / (2 - exp(x * exp(x))).
%F A328488 a(0) = 1; a(n) = Sum_{k=1..n} binomial(n,k) * A000248(k) * a(n-k).
%F A328488 a(n) ~ n! / (2*log(2) * (1 + LambertW(log(2))) * LambertW(log(2))^n). - _Vaclav Kotesovec_, Oct 17 2019
%t A328488 nmax = 19; CoefficientList[Series[1/(2 - Exp[x Exp[x]]), {x, 0, nmax}], x] Range[0, nmax]!
%Y A328488 Cf. A000248, A000670, A003725, A007550, A083355, A292952.
%K A328488 nonn
%O A328488 0,3
%A A328488 _Ilya Gutkovskiy_, Oct 16 2019