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%I #4 Mar 31 2012 12:37:34
%S 1,16,576,49472,10026880,4815077632,5473511562368,14733719832477184,
%T 93906982985442212608,1417227544723589396820800
%N Number of (n+1)X(n+1) 0..3 symmetric matrices 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..1..1....0..1..1..3....0..1..1..0....0..1..3..2....0..1..1..2
%e ..1..2..3..2....1..2..0..0....1..2..0..2....1..2..3..0....1..2..3..1
%e ..1..3..1..2....1..0..3..1....1..0..1..0....3..3..0..2....1..3..0..3
%e ..1..2..2..3....3..0..1..2....0..2..0..3....2..0..2..1....2..1..3..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 27 2012