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 A293905 #19 Oct 21 2017 07:47:09
%S A293905 1,1,2,8,44,316,2656,26632,299408,3809744,53425376,823627456,
%T A293905 13758271552,248997717568,4826005005824,100042516509056,
%U A293905 2204677070418176,51515128563296512,1270613780164684288,33020423388135645184,900956861702008749056
%N A293905 E.g.f.: exp(Sum_{n>=1} A000041(n-1)*x^n/n).
%H A293905 Seiichi Manyama, <a href="/A293905/b293905.txt">Table of n, a(n) for n = 0..433</a>
%F A293905 a(0) = 1 and a(n) = (n-1)! * Sum_{k=1..n} A000041(k-1)*a(n-k)/(n-k)! for n > 0.
%Y A293905 Cf. A000041, A293527.
%K A293905 nonn
%O A293905 0,3
%A A293905 _Seiichi Manyama_, Oct 19 2017