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%I #6 Mar 22 2013 18:13:50
%S 64,4096,204800,10240000,512000000,25600000000,1280000000000,
%T 64000000000000,3200000000000000,160000000000000000,
%U 8000000000000000000,400000000000000000000,20000000000000000000000,1000000000000000000000000
%N Number of nX3 0..3 arrays with antidiagonals unimodal
%C Column 3 of A223585
%H R. H. Hardin, <a href="/A223580/b223580.txt">Table of n, a(n) for n = 1..210</a>
%F Let U(z) = (z^6+15*z^5+115*z^4+405*z^3+964*z^2+660*z+720)/720
%F a(n) = U(min(n,3))^(max(n,3)-min(n,3)+1) * product{ U(i)^2 , i=1..(min(n,3)-1) }
%F a(n) = 50*a(n-1) for n>2
%e Some solutions for n=3
%e ..2..2..1....2..0..3....2..3..0....0..2..1....2..2..0....0..1..0....0..3..0
%e ..3..1..3....3..3..3....0..1..1....0..1..1....1..3..1....1..3..0....2..1..0
%e ..2..0..2....1..1..0....3..1..2....1..3..0....2..3..0....3..2..1....0..3..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 22 2013
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