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Number of nX2 0..2 arrays with no more than floor(nX2/2) elements equal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order
1

%I #5 Mar 16 2013 06:14:24

%S 1,7,31,187,990,5721,32155,185667,1068413,6209614,36152732,211488161,

%T 1240108650,7292753853,42976317875,253780411459,1501160467318,

%U 8893657851979,52763660745169,313428125418614,1863953435747000

%N Number of nX2 0..2 arrays with no more than floor(nX2/2) elements equal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order

%C Column 2 of A223149

%H R. H. Hardin, <a href="/A223144/b223144.txt">Table of n, a(n) for n = 1..192</a>

%e Some solutions for n=3

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

%e ..1..0....1..2....2..2....2..2....1..0....2..1....2..0....0..2....2..0....2..1

%e ..2..1....0..1....0..2....2..0....2..1....1..2....2..2....1..0....2..1....0..1

%K nonn

%O 1,2

%A _R. H. Hardin_ Mar 16 2013