%I #5 Mar 31 2012 12:37:06
%S 15,1750,1080457,2423004172,21200252524407
%N Number of (n+1)X(n+1) 0..3 arrays with no 2X2 subblock having the same number of equal edges as its horizontal or vertical neighbors, and new values 0..3 introduced in row major order
%C Diagonal of A205352
%e Some solutions for n=4
%e ..0..0..1..2..0....0..0..0..1..0....0..0..0..1..1....0..1..0..2..1
%e ..3..0..2..3..3....0..0..2..3..3....2..0..0..0..2....3..0..0..1..0
%e ..0..2..2..0..0....1..2..0..3..0....0..3..3..1..3....2..0..0..1..3
%e ..0..0..3..2..1....0..1..0..3..1....1..3..3..1..0....3..2..1..3..3
%e ..0..0..3..0..2....2..1..0..2..3....3..0..1..0..0....3..0..2..3..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 26 2012