A140913 Number of 4 X 8 matrices with elements in 0..n with each row and each column in nondecreasing order. 4,8,n can be permuted, see formula.

1, 495, 70785, 4723719, 184225041, 4789851066, 90474964580, 1318349483880, 15484613937936, 151561524301616, 1268665346776464, 9271015995674160, 60142744792450320, 351141102288229176, 1866359220145419780, 9118323640906544350, 41286527321442170625

Offset

0,2

Links

Table of n, a(n) for n=0..16.

Formula

(empirical) set p,q,r to n,8,4 (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: A027808 A104478 A133352 * A214555 A333756 A179170

Adjacent sequences: A140910 A140911 A140912 * A140914 A140915 A140916

Keyword

nonn

Author

R. H. Hardin, Jul 05 2008

Status

approved