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%I #5 Mar 31 2012 12:37:32
%S 1,201,89293,101095392,343737526300,3748133016211929,
%T 134623935213997208181,16106430235512371314453933
%N Number of (n+1)X(n+1) 0..3 arrays containing all values 0..3 with every 2X2 subblock having two or four distinct values, and new values 0..3 introduced in row major order
%C Diagonal of A210174
%e Some solutions for n=4
%e ..0..1..1..1..0....0..0..1..0..1....0..0..0..1..1....0..0..0..0..1
%e ..0..0..1..0..1....1..0..0..0..1....1..1..0..0..0....0..1..0..1..0
%e ..0..1..0..1..1....2..3..3..0..0....0..1..0..1..0....2..3..2..3..2
%e ..1..0..0..0..0....2..2..2..1..0....0..0..1..0..0....2..2..2..2..3
%e ..1..0..2..0..3....3..2..0..3..2....2..0..1..0..3....0..0..0..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 18 2012