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%I #5 Dec 18 2015 18:17:43
%S 8,225,12385,2332419,1850486123,6771682819965,107524741264745861,
%T 7041765967963842788487
%N Number of n X n symmetric 0..7 arrays with no element equal to the sum or difference mod 8 of any two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..6..4..3..5....4..4..5..3....6..2..6..6....2..2..6..2....6..2..2..5
%e ..4..4..5..3....4..4..5..4....2..6..5..2....2..2..6..2....2..2..6..2
%e ..3..5..4..4....5..5..3..4....6..5..6..6....6..6..6..5....2..6..1..6
%e ..5..3..4..5....3..4..4..2....6..2..6..1....2..2..5..6....5..2..6..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Aug 05 2011
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