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%I #8 Dec 18 2015 18:18:31
%S 3,81,16038,16230456,64207683936,817235401137408,28907250609032395776,
%T 2535541672670058530700288,503424192483622111094950081536,
%U 209983768351036102380925723459562496
%N Number of n X n 0..2 arrays with antidiagonals unimodal
%C Diagonal of A223576
%H R. H. Hardin, <a href="/A223570/b223570.txt">Table of n, a(n) for n = 1..64</a>
%F Let U(z) = (z^4+6*z^3+23*z^2+18*z+24)/24
%F a(n) = U(n) * product{ U(i)^2 , i=1..(n-1) }
%e Some solutions for n=3
%e ..1..0..2....0..2..1....2..1..2....1..0..2....0..0..0....1..2..0....0..0..0
%e ..1..1..2....1..1..1....2..2..0....1..0..1....0..1..0....0..1..0....1..0..2
%e ..1..1..0....0..0..0....2..1..1....0..1..2....1..1..1....2..0..0....0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 22 2013