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%I #4 Mar 31 2012 12:37:34
%S 0,5,536,69967,14851443,5745072271,4267026118300,6252252369058803,
%T 18347836198388369328,108778622095860972769932
%N Number of (n+1)X(n+1) 0..3 symmetric matrices containing all values 0..3 with every 2X2 subblock having one, two or four distinct values, and new values 0..3 introduced in lower triangle row major order
%e Some solutions for n=3
%e ..0..0..2..3....0..0..2..2....0..1..0..0....0..1..2..3....0..1..2..1
%e ..0..1..3..2....0..1..3..3....1..1..1..0....1..0..3..2....1..0..3..0
%e ..2..3..3..3....2..3..1..1....0..1..2..3....2..3..3..2....2..3..0..0
%e ..3..2..3..1....2..3..1..2....0..0..3..2....3..2..2..2....1..0..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 27 2012