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%I #4 Mar 31 2012 12:36:08
%S 192,13726,5098224,3387715318,19708386669940,150657364854061134
%N Number of (n+1)X(n+1) 0..3 arrays with all the 2X2 subblocks nonsingular and the array of 2X2 subblock determinants symmetric
%C Column 3 of A187462
%e Some solutions for 5X5
%e ..0..2..2..0..1....0..2..2..0..1....0..2..2..0..1....0..2..2..0..2
%e ..2..2..0..2..1....2..2..0..2..0....2..2..0..2..1....2..2..0..2..2
%e ..2..0..1..0..1....2..0..3..0..2....2..0..3..0..3....2..0..2..0..1
%e ..0..2..0..1..3....0..2..0..2..1....0..2..0..2..1....0..2..0..2..0
%e ..1..2..1..2..3....1..2..2..1..0....1..1..3..3..3....2..1..1..3..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 10 2011
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