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 A113373 #5 Jun 13 2017 23:21:07 %S A113373 1,10,190,4945,163705,6617605,317416204,17677189426,1123660618048, %T A113373 80411135580587,6405386721320372,562632770359355432, %U A113373 54061761393693393203,5643864294810397451552,636388356169482970183598 %N A113373 Column 3 of triangle A113370, also equals column 0 of A113370^10. %C A113373 Column k of A113370 = column 0 of A113370^(3*k+1) for k>=0. %o A113373 (PARI) a(n)=local(A,B);A=Mat(1);for(m=2,n+4,B=matrix(m,m); for(i=1,m, for(j=1,i,if(i<3 || j==i || j>m-1,B[i,j]=1,if(j==1, B[i,1]=1,B[i,j]=(A^(3*j-2))[i-j+1,1]));));A=B);A[n+4,4] %Y A113373 Cf. A113370, A113371 (column 1), A113372 (column 2). %K A113373 nonn %O A113373 0,2 %A A113373 _Paul D. Hanna_, Nov 13 2005