%I #3 Oct 03 2013 09:33:13
%S 1,48620,449141836,1371597504992,1832516612010448,1274867710694037824,
%T 520384188062967417280
%N Number of 9 X 9 matrices with elements in 0..n with each row and each column in nondecreasing order. 9,9,n can be permuted, see formula.
%F (empirical) set p,q,r to n,9,9 (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))
%K nonn
%O 0,2
%A _R. H. Hardin_, Jul 05 2008
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