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%I #8 Nov 20 2018 16:32:20
%S 784,3097,11116,37333,120304,377857,1167796,3572173,10854424,32839417,
%T 99070876,298318213,897166144,2695921777,8096612356,24307531453,
%U 72957983464,218944728937,656975744236,1971210347893,5914197274384
%N Number of (n+1) X (5+1) 0..2 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.
%H R. H. Hardin, <a href="/A250809/b250809.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 11*a(n-2) + 6*a(n-3); a(n) = (1131*3^n - 1080*2^n + 335)/2.
%F Empirical g.f.: x*(784 - 1607*x + 1158*x^2) / ((1 - x)*(1 - 2*x)*(1 - 3*x)). - _Colin Barker_, Nov 20 2018
%e Some solutions for n=4:
%e ..1..1..1..1..0..0....2..2..2..2..1..1....2..1..1..1..1..0....2..2..2..2..2..1
%e ..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..1..1..1..1
%e ..2..2..2..2..2..2....0..0..0..0..0..0....0..0..0..0..0..0....1..1..1..1..1..1
%e ..0..1..1..1..1..1....1..1..1..1..1..1....0..0..0..0..0..1....0..1..1..1..1..1
%e ..0..1..2..2..2..2....0..1..1..1..2..2....0..0..1..1..1..2....0..1..1..1..1..2
%Y Column 5 of A250812.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 27 2014
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