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%I #4 Nov 20 2013 18:51:25
%S 15,109,685,4483,29469,193531,1270657,8343063,54780825,359691769,
%T 2361740413,15507217849,101820594071,668555339287,4389743011111,
%U 28823109441929,189252909756115,1242637055605621,8159170994793111
%N Number of (n+1)X(1+1) 0..2 arrays with every element both >= and <= some horizontal, vertical or antidiagonal neighbor
%C Column 1 of A232204
%H R. H. Hardin, <a href="/A232197/b232197.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -5*a(n-2) +16*a(n-3) -12*a(n-4) -a(n-5) -7*a(n-6) -9*a(n-7) +2*a(n-8) -2*a(n-9) +3*a(n-10) +2*a(n-11) -a(n-12)
%e Some solutions for n=6
%e ..1..0....1..0....0..0....0..0....0..0....0..0....0..2....1..1....0..2....1..0
%e ..2..0....1..0....0..2....0..0....2..0....2..2....0..2....0..0....0..2....1..0
%e ..2..1....1..1....2..2....0..0....2..1....1..2....0..0....0..1....0..1....0..1
%e ..2..0....1..0....1..1....0..2....2..2....1..1....2..2....1..1....1..0....2..2
%e ..2..0....0..0....0..0....2..2....2..0....0..0....1..0....1..1....0..1....2..2
%e ..0..1....0..2....0..1....2..1....0..2....0..0....0..2....1..2....0..1....1..0
%e ..1..1....2..2....0..1....0..0....1..2....0..0....1..2....1..2....0..0....1..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 20 2013