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%I #5 Dec 18 2015 18:17:41
%S 0,1,37,2239,569881,907290415
%N Number of n X n symmetric 0..6 arrays with each element equal to the sum mod 7 of two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..4..2..1..6....0..0..0..0....1..4..3..4....1..4..1..3....2..1..5..2
%e ..2..5..6..5....0..0..0..0....4..1..6..1....4..3..5..2....1..6..3..4
%e ..1..6..1..2....0..0..4..4....3..6..3..4....1..5..4..6....5..3..6..1
%e ..6..5..2..4....0..0..4..1....4..1..4..1....3..2..6..5....2..4..1..2
%K nonn
%O 1,3
%A _R. H. Hardin_ Jul 16 2011