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A250793 Number of (n+1) X (4+1) 0..1 arrays with nondecreasing min(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 A250793 #8 Nov 20 2018 09:54:52
%S A250793 118,376,1190,3776,12062,38676,124366,400616,1292134,4171276,13474406,
%T A250793 43546448,140781326,455247108,1472416318,4762930232,15408574198,
%U A250793 49852141564,161298304598,521908159904,1688775756830,5464620624372
%N A250793 Number of (n+1) X (4+1) 0..1 arrays with nondecreasing min(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 A250793 R. H. Hardin, <a href="/A250793/b250793.txt">Table of n, a(n) for n = 1..210</a>
%F A250793 Empirical: a(n) = 8*a(n-1) - 20*a(n-2) + 8*a(n-3) + 33*a(n-4) - 36*a(n-5) + 8*a(n-7).
%F A250793 Empirical g.f.: 2*x*(59 - 284*x + 271*x^2 + 416*x^3 - 624*x^4 + 10*x^5 + 128*x^6) / ((1 - x)^2*(1 - 2*x)*(1 - 2*x - x^2)*(1 - 2*x - 4*x^2)). - _Colin Barker_, Nov 20 2018
%e A250793 Some solutions for n=4:
%e A250793 ..1..0..0..1..0....0..0..0..1..0....0..0..0..1..0....1..1..1..0..1
%e A250793 ..1..1..1..0..1....0..0..0..0..1....0..0..0..1..0....1..1..1..0..0
%e A250793 ..1..1..1..0..1....0..0..0..1..0....0..0..0..0..1....1..1..1..0..1
%e A250793 ..1..1..1..0..1....0..0..0..0..1....0..0..1..1..0....1..1..1..1..0
%e A250793 ..1..1..1..0..1....0..0..0..1..0....0..0..1..1..0....1..1..1..1..1
%Y A250793 Column 4 of A250797.
%K A250793 nonn
%O A250793 1,1
%A A250793 _R. H. Hardin_, Nov 27 2014