%I #4 Nov 26 2014 18:14:30
%S 104,520,2512,11736,53032,233300,1005121,4260728,17835379,73930174,
%T 304111433,1243471948,5060483311,20518170938,82950532885,334582615528,
%U 1347111707003,5416107760342,21751360774177,87278063198468
%N Number of (n+1)X(1+1) 0..3 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
%C Column 1 of A250676
%H R. H. Hardin, <a href="/A250669/b250669.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n-1) -106*a(n-2) +376*a(n-3) -769*a(n-4) +904*a(n-5) -564*a(n-6) +144*a(n-7) for n>11
%e Some solutions for n=4
%e ..2..1....2..0....0..2....2..0....0..0....0..0....1..1....1..0....2..1....0..1
%e ..0..3....1..2....1..1....1..1....0..2....0..1....0..2....0..1....0..3....0..3
%e ..2..1....1..2....1..1....0..2....1..1....1..3....1..3....0..1....0..3....0..3
%e ..3..0....2..1....2..2....0..2....2..2....2..2....2..2....0..3....3..0....2..1
%e ..0..3....2..2....1..3....1..1....3..1....2..3....2..2....2..1....0..3....1..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 26 2014
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