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%I #8 Dec 09 2018 07:28:49
%S 39,72,88,120,192,336,624,1200,2352,4656,9264,18480,36912,73776,
%T 147504,294960,589872,1179696,2359344,4718640,9437232,18874416,
%U 37748784,75497520,150994992,301989936,603979824,1207959600,2415919152,4831838256
%N Number of (n+1) X (2+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.
%H R. H. Hardin, <a href="/A253153/b253153.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) + 48 for n>3.
%F Empirical g.f.: x*(39 - 45*x - 50*x^2 + 8*x^4) / ((1 - x)*(1 - 2*x)). - _Colin Barker_, Dec 09 2018
%e Some solutions for n=6:
%e ..0..1..1....1..1..1....0..1..1....0..0..0....0..0..0....0..1..1....1..1..1
%e ..1..1..1....1..1..1....1..1..1....1..1..1....1..1..1....0..0..0....0..0..0
%e ..1..1..1....0..0..0....1..0..0....1..1..1....1..1..1....1..1..1....1..1..1
%e ..0..0..0....1..1..1....1..0..0....0..0..0....0..0..0....1..1..1....0..0..0
%e ..0..0..0....1..1..1....1..0..0....1..1..1....1..1..1....0..0..0....1..1..1
%e ..1..1..1....0..0..0....1..0..0....0..0..0....1..1..1....1..1..1....0..0..0
%e ..1..1..1....0..0..0....0..0..1....0..0..0....1..1..1....0..0..1....0..0..0
%Y Column 2 of A253159.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 28 2014
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