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A250802 Number of (5+1) X (n+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 A250802 #8 Nov 20 2018 16:31:52
%S A250802 338,1336,4258,12062,31220,76110,177142,398704,874298,1879862,3980276,
%T A250802 8328038,17263070,35523840,72679858,148022462,300378084,607796942,
%U A250802 1227019286,2472564224,4975146938,9998914966,20076555908,40280556422
%N A250802 Number of (5+1) X (n+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 A250802 R. H. Hardin, <a href="/A250802/b250802.txt">Table of n, a(n) for n = 1..210</a>
%F A250802 Empirical: a(n) = 5*a(n-1) - 6*a(n-2) - 7*a(n-3) + 18*a(n-4) - 3*a(n-5) - 14*a(n-6) + 7*a(n-7) + 3*a(n-8) - 2*a(n-9).
%F A250802 Empirical g.f.: 2*x*(169 - 177*x - 197*x^2 + 577*x^3 - 137*x^4 - 423*x^5 + 221*x^6 + 95*x^7 - 64*x^8) / ((1 - x)^4*(1 + x)^2*(1 - 2*x)*(1 - x - x^2)). - _Colin Barker_, Nov 20 2018
%e A250802 Some solutions for n=4:
%e A250802 ..1..0..1..0..0....1..0..1..0..1....0..1..0..1..0....0..0..0..0..0
%e A250802 ..1..0..1..0..0....1..1..0..1..0....0..1..0..0..1....0..0..0..0..0
%e A250802 ..1..0..1..0..0....1..1..0..0..1....0..1..0..1..0....0..0..0..0..0
%e A250802 ..1..0..1..0..0....1..1..0..0..0....0..1..0..1..0....0..0..0..0..1
%e A250802 ..1..0..1..0..0....1..1..0..0..1....0..1..0..0..1....0..0..0..0..0
%e A250802 ..0..1..0..1..1....1..1..1..1..0....0..0..1..1..0....0..0..0..1..1
%Y A250802 Row 5 of A250797
%K A250802 nonn
%O A250802 1,1
%A A250802 _R. H. Hardin_, Nov 27 2014