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%I #7 Nov 15 2018 08:38:35
%S 120,290,592,1126,2092,3890,7320,13982,27076,53002,104560,207350,
%T 412572,822626,1642312,3281230,6558580,13112762,26220576,52435622,
%U 104865100,209723410,419439352,838870526,1677732132,3355454570,6710898640
%N Number of (n+1) X (4+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing x(i,j)-x(i-1,j) in the j direction.
%H R. H. Hardin, <a href="/A250607/b250607.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) - 9*a(n-2) + 7*a(n-3) - 2*a(n-4).
%F Empirical: a(n) = 100*2^(n-1) + 16*n^2 + 22*n - 18.
%F Empirical g.f.: 2*x*(60 - 155*x + 111*x^2 - 32*x^3) / ((1 - x)^3*(1 - 2*x)). - _Colin Barker_, Nov 15 2018
%e Some solutions for n=6:
%e ..1..1..0..0..0....0..0..0..0..0....1..1..0..0..0....1..1..1..1..0
%e ..1..1..0..0..0....1..1..1..1..1....1..1..0..0..0....1..1..1..1..0
%e ..1..1..1..1..1....0..0..0..0..0....1..1..1..1..1....1..1..1..1..1
%e ..1..1..1..1..1....0..0..0..0..1....1..1..1..1..1....1..1..1..1..1
%e ..0..0..0..0..0....0..0..0..0..1....0..0..0..0..0....0..0..0..0..0
%e ..0..0..0..0..0....0..0..0..0..1....0..1..1..1..1....1..1..1..1..1
%e ..0..1..1..1..1....0..0..0..0..1....0..1..1..1..1....1..1..1..1..1
%Y Column 4 of A250611.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 26 2014
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