A113388 Column 0 of triangle A113387, also equals column 0 of A113389^2.

1, 6, 48, 605, 11196, 280440, 8981460, 353283128, 16567072675, 905357065354, 56632746126107, 3997082539456084, 314584709388906568, 27340439653453247728, 2602372304420672868499, 269388182085308601450047

Offset: 0

Author

Paul D. Hanna, Nov 14 2005

Keywords

• nonn

Crossrefs

Cf. A113381, A113387, A113389.

Programs

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-1))[r-c+1,1]))^3)[n+1,1]

Formula

A113387 equals the matrix cube of A113381, which has the property: column k of A113381^3 = column 0 of A113389^(3*k+2) for k>=0.