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%I #6 Dec 18 2015 18:17:54
%S 1,4,9,59,2033,51688,4522496,559601114,174674654015
%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 0,2,1,0,0 for x=0,1,2,3,4
%C Every 0 is next to 0 0's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
%C Diagonal of A198185
%e Some solutions for n=4
%e ..0..2..1..1....0..3..0..1....1..0..3..0....1..0..2..1....1..0..1..2
%e ..1..1..0..2....1..0..3..2....2..3..0..1....2..1..1..0....2..1..0..1
%e ..2..0..1..1....2..1..0..1....1..0..1..2....2..1..0..1....0..1..1..0
%e ..1..1..2..0....0..1..2..1....1..2..1..0....1..0..1..2....1..2..2..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 21 2011