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Number of (n+1) X (5+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.
1

%I #8 Dec 09 2018 09:14:28

%S 181,192,201,236,308,452,740,1316,2468,4772,9380,18596,37028,73892,

%T 147620,295076,589988,1179812,2359460,4718756,9437348,18874532,

%U 37748900,75497636,150995108,301990052,603979940,1207959716,2415919268,4831838372

%N Number of (n+1) X (5+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.

%H R. H. Hardin, <a href="/A253156/b253156.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) + 164 for n>3.

%F Empirical g.f.: x*(181 - 351*x - 13*x^2 + 17*x^3 + 2*x^4) / ((1 - x)*(1 - 2*x)). - _Colin Barker_, Dec 09 2018

%e Some solutions for n=6:

%e ..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

%e ..0..0..0..0..0..0....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

%e ..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

%e ..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

%e ..1..1..1..1..1..1....0..0..0..0..0..0....1..0..1..0..0..1....1..0..0..0..0..0

%e ..0..0..0..0..0..0....0..0..0..0..0..0....1..0..1..0..0..1....1..0..0..0..0..0

%e ..0..0..0..0..0..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

%Y Column 5 of A253159.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 28 2014