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 A113395 #5 Jun 13 2017 23:30:38 %S A113395 1,9,99,1569,34344,980487,34930455,1502349459,76058669082, %T A113395 4443563603890,294878418586620,21942670402467153,1811533845177895161, %U A113395 164451065361854357011,16291788187615516225925 %N A113395 Column 0 of triangle A113394, which equals the matrix cube of A113389. %F A113395 Column k of A113389^3 = column 0 of A113389^(3*k+3) for k>=0. %o A113395 (PARI) a(n)=local(A,B);A=Mat(1);for(m=2,n+1,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); (matrix(#A,#A,r,c,if(r>=c,(A^(3*c))[r-c+1,1]))^3)[n+1,1] %Y A113395 Cf. A113389, A113394. %K A113395 nonn %O A113395 0,2 %A A113395 _Paul D. Hanna_, Nov 14 2005