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%I #6 Dec 18 2015 18:17:48
%S 1,6,40,1142,56137,9202067,3464871506,3526366342860
%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 4,0,2,1,3 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 2's, every 3 is next to 3 1's, every 4 is next to 4 3's
%C Diagonal of A196718
%e Some solutions for n=4
%e ..0..0..0..1....2..2..0..0....2..2..2..1....1..0..0..1....1..0..1..1
%e ..1..3..1..3....2..2..1..1....2..0..2..0....1..1..1..1....3..1..1..0
%e ..3..1..1..1....0..1..1..3....2..2..2..0....0..1..3..0....1..1..1..0
%e ..1..0..0..0....1..1..0..1....0..0..0..0....0..1..1..0....0..0..1..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 05 2011