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%I #8 Nov 19 2018 12:59:24
%S 36,96,230,534,1194,2604,5568,11732,24442,50482,103566,211360,429580,
%T 870280,1758574,3546318,7139858,14356148,28835992,57872156,116068226,
%U 232660586,466169270,933710824,1869642084,3742876944,7491567158
%N Number of (3+1) X (n+1) 0..1 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.
%H R. H. Hardin, <a href="/A250785/b250785.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) - 8*a(n-2) + 3*a(n-3) + 3*a(n-4) - 2*a(n-5).
%F Empirical g.f.: 2*x*(18 - 42*x + 19*x^2 + 22*x^3 - 16*x^4) / ((1 - x)^2*(1 - 2*x)*(1 - x - x^2)). - _Colin Barker_, Nov 19 2018
%e Some solutions for n=4:
%e ..1..0..1..0..0....1..0..0..0..1....1..0..0..0..1....0..0..0..1..0
%e ..1..0..1..0..1....1..0..0..0..1....1..0..0..0..1....0..0..1..0..1
%e ..1..0..1..0..1....1..0..0..1..0....1..0..1..1..0....1..1..0..1..0
%e ..0..1..0..1..0....1..0..0..1..1....1..0..1..1..0....1..1..1..0..1
%Y Row 3 of A250783.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 27 2014
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