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 A112913 #3 Mar 30 2012 18:36:51
%S A112913 1,3,15,96,729,6327,61380,655944,7642557,96338925,1306003803,
%T A112913 18947038404,292956751236,4810423131828,83620543389804,
%U A112913 1534493081643552,29649997606132197,601828286370137865,12804746026265284149
%N A112913 Column 2 of triangle A112911.
%F A112913 a(n) = Sum_{k=0..n-1} (n-k+2)*A088716(k)*a(n-k-1) for n>0 with a(0)=1.
%o A112913 (PARI) {a(n)=local(A=Mat(1),B);for(m=2,n+3,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i,B[i,j]=1,B[i,j]=-j*(A^-1)[i-j,1]);));A=B);return((A^-1)[n+3,3])}
%Y A112913 Cf. A112911 (triangle), A088716 (column 0), A112912 (column 1), A112914 (column 3).
%K A112913 nonn
%O A112913 0,2
%A A112913 _Paul D. Hanna_, Oct 06 2005