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%I #8 Dec 16 2018 08:37:43
%S 132,260,428,636,884,1172,1500,1868,2276,2724,3212,3740,4308,4916,
%T 5564,6252,6980,7748,8556,9404,10292,11220,12188,13196,14244,15332,
%U 16460,17628,18836,20084,21372,22700,24068,25476,26924,28412,29940,31508,33116
%N Number of (n+2) X (1+2) 0..1 arrays with every 2 X 2 and 3 X 3 subblock diagonal maximum minus antidiagonal minimum nondecreasing horizontally and vertically.
%H R. H. Hardin, <a href="/A253503/b253503.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 20*n^2 + 68*n + 44.
%F Conjectures from _Colin Barker_, Dec 16 2018: (Start)
%F G.f.: 4*x*(33 - 34*x + 11*x^2) / (1 - x)^3.
%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>3.
%F (End)
%e Some solutions for n=4:
%e ..0..1..1....0..1..1....1..1..1....0..0..0....0..0..0....0..1..1....0..1..0
%e ..1..1..0....0..0..1....1..1..0....1..1..1....0..0..0....1..1..1....1..1..0
%e ..1..1..0....0..0..1....1..1..0....0..0..0....0..0..0....1..1..1....1..1..0
%e ..1..1..0....1..0..1....1..1..1....1..1..1....0..0..0....1..1..0....0..0..0
%e ..1..1..0....1..0..1....1..0..1....0..0..0....0..0..0....1..1..1....1..1..1
%e ..0..1..1....0..0..1....0..0..1....0..1..1....0..1..1....0..0..0....0..0..1
%Y Column 1 of A253510.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 02 2015