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%I #4 Mar 31 2012 12:37:34
%S 0,12,551,49223,10022877,4814973856,5473507216675,14733719538503109,
%T 93906982953302482787,1417227544717910923643049
%N Number of (n+1)X(n+1) 0..3 symmetric matrices containing all values 0..3 with every 2X2 subblock having three distinct values, and new values 0..3 introduced in lower triangle row major order
%e Some solutions for n=3
%e ..0..1..3..3....0..1..1..3....0..1..1..2....0..1..2..1....0..1..1..1
%e ..1..2..1..2....1..2..0..1....1..2..0..1....1..2..0..0....1..2..0..3
%e ..3..1..0..2....1..0..3..0....1..0..1..2....2..0..1..3....1..0..3..2
%e ..3..2..2..1....3..1..0..2....2..1..2..3....1..0..3..2....1..3..2..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 27 2012