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%I #7 Nov 27 2018 16:17:18
%S 3264,164800,8320896,420152704,21215177472,1071238805248,
%T 54091113672192,2731275752121856,137912990258285568,
%U 6963776128082148352,351628790523862185984,17755138024422940530688,896527630165476145606656
%N Number of (n+1) X (2+1) 0..3 arrays with no 2 X 2 subblock having its maximum diagonal element less than its minimum antidiagonal element.
%H R. H. Hardin, <a href="/A251277/b251277.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 54*a(n-1) - 182*a(n-2) + 228*a(n-3) + 1152*a(n-4).
%F Empirical g.f.: 64*x*(51 - 179*x + 246*x^2 + 1152*x^3) / (1 - 54*x + 182*x^2 - 228*x^3 - 1152*x^4). - _Colin Barker_, Nov 27 2018
%e Some solutions for n=2:
%e ..0..0..2....3..0..0....1..3..2....1..2..0....1..3..0....1..1..3....1..3..0
%e ..1..2..3....3..1..1....0..2..2....2..3..2....0..0..1....0..1..1....0..0..2
%e ..0..0..3....3..0..3....0..1..3....3..3..2....2..1..2....2..1..0....2..3..3
%Y Column 2 of A251283.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 01 2014
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