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%I #5 Mar 31 2012 12:37:32
%S 0,1091,1575467,11061291451,437971830335043,98959142504758664603,
%T 127648944948853198818703027,940014634185937826679488616180507
%N Number of (n+1)X(n+1) 0..3 arrays containing all values 0..3 with every 2X2 subblock having one or three distinct values, and new values 0..3 introduced in row major order
%C Diagonal of A210309
%e Some solutions for n=4
%e ..0..0..0..0..1....0..0..0..0..1....0..1..0..0..0....0..1..0..0..0
%e ..2..1..3..1..2....2..3..1..2..0....0..2..1..3..2....0..2..0..0..0
%e ..1..3..2..2..0....2..0..0..1..2....1..1..3..0..3....3..2..3..1..2
%e ..2..2..1..3..0....3..2..1..2..3....2..3..0..1..0....1..1..2..1..3
%e ..1..3..2..2..2....1..1..3..1..2....2..1..3..3..0....0..2..0..1..2
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 19 2012