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%I
%S 0,2,8,127,3686,285929,47398400,18127384939,15993244772677,
%T 32531416116323498,152344987111028997103,1640044640940871976733780
%N Number of n X n symmetric 0..2 arrays with each element equal to the product mod 3 of two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..1..2..1..2....1..2..2..1....1..2..0..0....1..1..1..1....1..2..1..1
%e ..2..2..1..2....2..2..1..2....2..2..1..0....1..1..1..1....2..2..1..1
%e ..1..1..1..2....2..1..1..2....0..1..2..2....1..1..1..0....1..1..1..1
%e ..2..2..2..1....1..2..2..1....0..0..2..1....1..1..0..0....1..1..1..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Jul 27 2011
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