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A250770 Number of (2+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.

%I A250770 #11 Nov 19 2018 07:18:47
%S A250770 18,34,62,114,214,410,798,1570,3110,6186,12334,24626,49206,98362,
%T A250770 196670,393282,786502,1572938,3145806,6291538,12582998,25165914,
%U A250770 50331742,100663394,201326694,402653290,805306478,1610612850,3221225590
%N A250770 Number of (2+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 A250770 R. H. Hardin, <a href="/A250770/b250770.txt">Table of n, a(n) for n = 1..210</a>
%F A250770 Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3); a(n) = 12*2^(n-1) + 4*n + 2.
%F A250770 Empirical g.f.: 2*x*(9 - 19*x + 8*x^2) / ((1 - x)^2*(1 - 2*x)). - _Colin Barker_, Nov 19 2018
%e A250770 Some solutions for n=4:
%e A250770 ..0..0..1..0..0....1..0..0..0..0....1..0..0..1..1....1..0..0..0..0
%e A250770 ..0..0..1..0..0....1..0..0..0..0....1..0..0..1..1....1..0..0..0..0
%e A250770 ..0..0..1..0..1....1..0..0..0..0....1..0..0..1..1....0..1..1..1..1
%Y A250770 Row 2 of A250769.
%K A250770 nonn
%O A250770 1,1
%A A250770 _R. H. Hardin_, Nov 27 2014