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A250741 Number of (n+1) X (7+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nonincreasing x(i,j)-x(i-1,j) in the j direction.

%I A250741 #11 Aug 19 2025 08:42:34
%S A250741 258,262,270,286,318,382,510,766,1278,2302,4350,8446,16638,33022,
%T A250741 65790,131326,262398,524542,1048830,2097406,4194558,8388862,16777470,
%U A250741 33554686,67109118,134217982,268435710,536871166,1073742078,2147483902,4294967550,8589934846,17179869438
%N A250741 Number of (n+1) X (7+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nonincreasing x(i,j)-x(i-1,j) in the j direction.
%H A250741 R. H. Hardin, <a href="/A250741/b250741.txt">Table of n, a(n) for n = 1..210</a>
%F A250741 Empirical: a(n) = 3*a(n-1) - 2*a(n-2); a(n) = 2^(n+1) + 254.
%F A250741 Empirical g.f.: 2*x*(129 - 256*x) / ((1 - x)*(1 - 2*x)). - _Colin Barker_, Nov 17 2018
%e A250741 Some solutions for n=4:
%e A250741 ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....1..0..0..1..0..1..1..0
%e A250741 ..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1....1..0..0..1..0..1..1..0
%e A250741 ..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1....1..0..0..1..0..1..1..0
%e A250741 ..1..1..1..1..1..1..1..1....0..0..0..0..0..0..0..0....1..0..0..1..0..1..1..0
%e A250741 ..0..0..0..0..0..0..0..0....1..1..1..1..1..1..1..1....1..0..0..1..0..1..1..0
%Y A250741 Column 7 of A250742.
%K A250741 nonn
%O A250741 1,1
%A A250741 _R. H. Hardin_, Nov 27 2014