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 A293906 #11 Oct 21 2017 07:47:25
%S A293906 1,1,2,6,30,174,1284,11148,110604,1215180,15066936,205333416,
%T A293906 3031876872,48536481096,834192650160,15357616617744,301627633467024,
%U A293906 6274718094035088,137885714638938144,3199063553591292000,77943291010448903136,1991687512094232297696
%N A293906 E.g.f.: exp(Sum_{n>=1} A000009(n-1)*x^n/n).
%H A293906 Seiichi Manyama, <a href="/A293906/b293906.txt">Table of n, a(n) for n = 0..439</a>
%F A293906 a(0) = 1 and a(n) = (n-1)! * Sum_{k=1..n} A000009(k-1)*a(n-k)/(n-k)! for n > 0.
%Y A293906 Cf. A000009, A293528.
%K A293906 nonn
%O A293906 0,3
%A A293906 _Seiichi Manyama_, Oct 19 2017