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%I #6 Dec 18 2015 18:17:41
%S 4,27,201,2791,77245,4482957,547681823,138848752487,71804214564925,
%T 74948295541392333,157072100264370812423,659458569446754937883175,
%U 5541778577891773501263989795,93184605443427688066128310380963
%N Number of n X n symmetric 0..3 arrays with no element equal to the sum mod 4 of any two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..1..1..3..3....1..1..1..3....3..3..1..3....1..3..3..3....3..3..1..3
%e ..1..3..1..1....1..3..1..3....3..3..3..1....3..3..1..3....3..1..3..1
%e ..3..1..1..1....1..1..1..1....1..3..3..1....3..1..3..1....1..3..1..3
%e ..3..1..1..1....3..3..1..3....3..1..1..3....3..3..1..1....3..1..3..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 18 2011