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%I #5 Dec 18 2015 18:17:41
%S 0,1,25,1061,200989,167167273,476648665905,5119795667808469
%N Number of n X n symmetric 0..4 arrays with each element equal to the sum mod 5 of two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..2..1..3..0....4..2..1..3....3..4..1..2....2..1..0..0....4..2..3..3
%e ..1..4..2..2....2..3..4..2....4..2..3..1....1..1..0..0....2..4..1..0
%e ..3..2..0..0....1..4..0..0....1..3..2..4....0..0..1..1....3..1..2..2
%e ..0..2..0..0....3..2..0..0....2..1..4..3....0..0..1..2....3..0..2..4
%K nonn
%O 1,3
%A _R. H. Hardin_ Jul 16 2011