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A250775 Number of (7+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 A250775 #8 Nov 19 2018 09:13:52
%S A250775 576,1026,1622,2396,3412,4798,6810,9960,15272,24794,42622,76948,
%T A250775 144156,277014,541058,1067360,2118064,4217458,8414118,16805196,
%U A250775 33584996,67142126,134253802,268474456,536912952,1073787018,2147532110,4295019140
%N A250775 Number of (7+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 A250775 R. H. Hardin, <a href="/A250775/b250775.txt">Table of n, a(n) for n = 1..210</a>
%F A250775 Empirical: a(n) = 5*a(n-1) - 9*a(n-2) + 7*a(n-3) - 2*a(n-4); a(n) = 32*2^(n-1) + 57*n^2 + 247*n + 240.
%F A250775 Empirical g.f.: 2*x*(288 - 927*x + 838*x^2 - 256*x^3) / ((1 - x)^3*(1 - 2*x)). - _Colin Barker_, Nov 19 2018
%e A250775 Some solutions for n=4:
%e A250775 ..0..0..1..0..0....1..1..1..1..0....0..0..0..0..0....1..1..1..0..0
%e A250775 ..0..0..1..0..0....1..1..1..1..0....0..0..0..0..0....1..1..1..1..1
%e A250775 ..0..0..1..0..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
%e A250775 ..0..0..1..0..0....0..0..0..0..0....1..1..1..1..1....0..0..0..0..0
%e A250775 ..0..0..1..0..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
%e A250775 ..0..0..1..0..0....1..1..1..1..1....0..0..0..0..0....1..1..1..1..1
%e A250775 ..0..0..1..0..0....1..1..1..1..1....0..0..0..0..1....1..1..1..1..1
%e A250775 ..0..0..1..0..1....1..1..1..1..1....0..0..0..0..1....0..0..0..0..0
%Y A250775 Row 7 of A250769.
%K A250775 nonn
%O A250775 1,1
%A A250775 _R. H. Hardin_, Nov 27 2014