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%I #8 Nov 18 2018 09:09:20
%S 68,114,196,350,648,1234,2396,4710,9328,18554,36996,73870,147608,
%T 295074,589996,1179830,2359488,4718794,9437396,18874590,37748968,
%U 75497714,150995196,301990150,603980048,1207959834,2415919396,4831838510
%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 absolute value of x(i,j)-x(i-1,j) in the j direction.
%H R. H. Hardin, <a href="/A250765/b250765.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3); a(n) = 36*2^(n-1) + 10*n + 22.
%F Empirical g.f.: 2*x*(34 - 79*x + 40*x^2) / ((1 - x)^2*(1 - 2*x)). - _Colin Barker_, Nov 18 2018
%e Some solutions for n=4:
%e ..1..1..0..0..0....1..1..1..1..0....1..1..1..1..1....1..0..1..0..0
%e ..1..1..0..0..0....1..1..1..1..0....0..0..0..0..0....1..0..1..0..0
%e ..1..1..1..1..1....1..1..1..1..0....0..0..0..0..0....1..0..1..0..0
%e ..1..1..1..1..1....1..1..1..1..0....0..0..0..0..0....1..0..1..0..1
%e ..1..1..1..1..1....1..1..1..1..0....1..1..1..1..1....1..0..1..0..1
%Y Column 4 of A250769.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 27 2014
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