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%I #4 Mar 31 2012 12:36:08
%S 104,3790,35026,220802,727842,2327574,5366230,13768228,28531154,
%T 54987216,90945478
%N Number of 4X4 0..n arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under 90 degree rotation
%C Row 3 of A187528
%e Some solutions for 4X4
%e ..3..1..2..1....3..3..1..3....3..0..3..1....2..3..3..3....2..1..0..1
%e ..1..0..1..0....2..3..0..3....1..2..0..2....1..0..1..0....2..0..2..1
%e ..0..1..0..1....1..0..1..0....3..0..3..3....3..3..0..3....0..1..0..1
%e ..1..0..1..0....0..3..0..3....0..2..0..2....1..0..1..2....2..3..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 10 2011