%I #5 Mar 31 2012 12:37:06
%S 15,1030,229445,146904738,219511132715,1046956456530150
%N Number of (n+1)X(n+1) 0..3 arrays with every 2X2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..3 introduced in row major order
%C Diagonal of A205609
%e Some solutions for n=4
%e ..0..0..0..1..0....0..0..1..2..1....0..0..0..0..1....0..0..1..0..0
%e ..2..2..0..0..0....1..1..1..2..1....1..0..2..0..1....2..3..3..3..1
%e ..0..1..1..3..1....3..0..3..2..3....0..2..3..1..0....3..3..0..3..1
%e ..0..0..1..3..1....2..1..2..0..1....3..2..0..1..2....1..2..2..2..2
%e ..3..2..2..2..2....1..1..2..0..1....0..1..2..3..0....1..1..1..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 29 2012
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