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%I #7 Dec 12 2018 06:25:22
%S 39,58,73,108,180,324,612,1188,2340,4644,9252,18468,36900,73764,
%T 147492,294948,589860,1179684,2359332,4718628,9437220,18874404,
%U 37748772,75497508,150994980,301989924,603979812,1207959588,2415919140,4831838244
%N Number of (n+1) X (2+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.
%H R. H. Hardin, <a href="/A253429/b253429.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) for n>5.
%F Empirical: a(n) = 9*2^(n-1) + 36 for n>3.
%F Empirical g.f.: x*(39 - 59*x - 23*x^2 + 5*x^3 + 2*x^4) / ((1 - x)*(1 - 2*x)). - _Colin Barker_, Dec 12 2018
%e Some solutions for n=4:
%e ..1..0..0....1..1..1....1..1..0....0..0..0....0..1..1....0..0..1....0..0..0
%e ..1..0..0....0..0..0....1..1..0....1..1..1....0..0..0....1..0..1....0..0..0
%e ..1..0..0....0..0..0....1..1..0....0..0..0....1..1..1....1..0..1....0..0..0
%e ..1..0..0....0..0..0....1..1..0....1..1..1....1..1..1....1..0..1....0..0..0
%e ..1..0..0....0..0..1....0..0..0....0..0..1....1..1..1....1..0..1....0..0..1
%Y Column 2 of A253435.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 31 2014
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