A113379 Column 0 of triangle A113378, also equals column 0 of A113389.

1, 3, 15, 136, 1998, 41973, 1166263, 40747561, 1726907675, 86421647389, 5002021986418, 329382745551946, 24351172588548270, 1999205882982496161, 180613538916429940159, 17817366508243503227269

Offset

0,2

Links

Table of n, a(n) for n=0..15.

Formula

A113378 equals the matrix cube of A113370, which has the property: column k of A113370^3 = column 0 of A113389^(3*k+1) 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); (A^3)[n+1, 1]

Crossrefs

Cf. A113378, A113370, A113389, A113380 (column 1).

Sequence in context: A028362 A195764 A113723 * A267018 A262911 A163949

Adjacent sequences: A113376 A113377 A113378 * A113380 A113381 A113382

Keyword

nonn

Author

Paul D. Hanna, Nov 14 2005

Status

approved