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 A106209 #4 Mar 30 2012 18:36:45
%S A106209 1,2,6,30,231,2453,33393,556999,11039026,254128870,6677972615,
%T A106209 197547561340,6504619941881,236165840696980,9380353293627619,
%U A106209 404848232250564042,18875601922237847288,945875935431064488637
%N A106209 Row sums of triangle A106208.
%o A106209 (PARI) {a(n)=local(A=matrix(1,1),B);A[1,1]=1; for(m=2,n+1,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i,B[i,j]=j,if(j==1,B[i,j]=(A^2)[i-1,1], B[i,j]=(A^2)[i-1,j]));));A=B); return(sum(k=0,n,A[n+1,k+1]/(k+1)))}
%Y A106209 Cf. A106208.
%K A106209 nonn
%O A106209 0,2
%A A106209 _Paul D. Hanna_, May 01 2005