A113395 Column 0 of triangle A113394, which equals the matrix cube of A113389.

1, 9, 99, 1569, 34344, 980487, 34930455, 1502349459, 76058669082, 4443563603890, 294878418586620, 21942670402467153, 1811533845177895161, 164451065361854357011, 16291788187615516225925

Offset

0,2

Links

Table of n, a(n) for n=0..14.

Formula

Column k of A113389^3 = column 0 of A113389^(3*k+3) for k>=0.

Prog

(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]

Crossrefs

Cf. A113389, A113394.

Sequence in context: A356100 A080291 A215243 * A070068 A068668 A035027

Adjacent sequences: A113392 A113393 A113394 * A113396 A113397 A113398

Keyword

nonn

Author

Paul D. Hanna, Nov 14 2005

Status

approved