A126467 Column 1 of triangle A126465.

1, 1, 6, 105, 3710, 219625, 19545316, 2437990653, 405899413380, 87002614878795, 23351252019790310, 7676367378822833691, 3035533054438876836390, 1422385798272704860377055, 779768824083518449340320720

Offset

0,3

Links

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

Prog

(PARI) {a(n)=local(M=matrix(n+2, n+2, r, c, if(r>=c, binomial((r-1)*r*(r+1)/3!-(c-1)*c*(c+1)/3!, r-c))), N=matrix(n+2, n+2, r, c, if(r>=c, binomial((r-1)*r*(r+1)/3!-(c-1)*c*(c+1)/3!+1, r-c)))); (N*M^-1)[n+2, 2]}

Crossrefs

Cf. A126465, A126466, A126468; A126469 (row sums).

Sequence in context: A221933 A110342 A227207 * A013294 A013300 A330769

Adjacent sequences: A126464 A126465 A126466 * A126468 A126469 A126470

Keyword

nonn

Author

Paul D. Hanna, Dec 27 2006

Status

approved