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%I #5 Mar 31 2012 12:37:31
%S 1,221,159327,363492269,3047709295897,100540191960863826,
%T 13475932703981552094893,7453689884209460671972584992
%N Number of (n+1)X(n+1) 0..3 arrays containing all values 0..3 with every 2X2 subblock having one, two or four distinct values, and new values 0..3 introduced in row major order
%C Diagonal of A210143
%e Some solutions for n=4
%e ..0..1..1..2..2....0..0..0..0..1....0..0..0..0..0....0..0..1..1..0
%e ..3..2..1..1..1....0..2..2..2..3....0..0..0..0..0....2..2..3..1..0
%e ..0..1..1..3..3....1..3..2..2..2....0..0..0..0..0....3..2..3..3..2
%e ..1..0..1..1..1....3..1..0..2..1....0..0..0..0..0....0..1..0..3..2
%e ..1..0..0..0..1....1..1..0..2..1....1..0..2..0..3....0..1..0..3..2
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 17 2012