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%I #6 Dec 18 2015 18:17:49
%S 1,9,68,5197,720447,337295264,529968166606,2583340386672393
%N Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,0,1,1,1 for x=0,1,2,3,4
%C Every 0 is next to 0 4's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
%C Diagonal of A197431
%e Some solutions containing all values 0 to 4 for n=4
%e ..2..1..0..1....1..0..0..0....1..2..0..0....0..1..2..0....1..3..1..0
%e ..1..4..1..1....1..3..1..2....0..1..1..1....1..4..1..0....0..1..4..1
%e ..0..1..1..0....0..1..4..1....0..1..4..1....3..1..1..0....0..2..1..3
%e ..0..1..3..1....0..2..1..0....1..3..1..0....1..0..1..1....0..0..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 14 2011