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 A113358 #5 Jun 13 2017 23:05:13 %S A113358 1,12,150,2184,37523,754171,17502145,462930509,13792292332, %T A113358 458112945183,16812390472566,676432435584855,29635374525536866, %U A113358 1405425902409792025,71770681806834337871,3928431507732054301085,229528875492540329214765 %N A113358 Column 2 of triangle A113355, also equals column 0 of A113355^3. %C A113358 A113355 equals the matrix square of A113350, where column 2 of A113350^2 = column 0 of A113350^6. %o A113358 (PARI) a(n)=local(A,B);A=matrix(1,1);A[1,1]=1;for(m=2,n+3,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^(2*j-1))[i-j+1,1]));));A=B); (matrix(#A,#A,r,c,if(r>=c,(A^(2*c))[r-c+1,1]))^2)[n+3,3] %Y A113358 Cf. A113340, A113350, A113355, A113356 (column 0), A113357 (column 1), A113359 (column 3). %K A113358 nonn %O A113358 0,2 %A A113358 _Paul D. Hanna_, Nov 08 2005