A140916 Number of 7 X 8 matrices with elements in 0..n with each row and each column in nondecreasing order. 7,8,n can be permuted, see formula.

1, 6435, 9202050, 4971151900, 1318349483880, 201299981193168, 19702998159210080, 1335119245893326400, 66345156372852988800

Offset

0,2

Links

Table of n, a(n) for n=0..8.

Formula

(empirical) set p,q,r to n,8,7 (in any order) in s=p+q+r-1; a(n) = product {i in 0..r-1} (binomial(s,p+i)*i!/(s-i)^(r-i-1))

Crossrefs

Sequence in context: A104318 A222344 A194720 * A208621 A294855 A025040

Adjacent sequences: A140913 A140914 A140915 * A140917 A140918 A140919

Keyword

nonn

Author

R. H. Hardin, Jul 05 2008

Status

approved