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%I #4 Mar 31 2012 12:36:09
%S 31,446,60,324452,70548,6090023738,720252796
%N Number of (n+1)X(n+1) 0..2 arrays with each 2X2 non-center subblock determinant nonzero and the array of 2X2 subblock determinants antisymmetric under 90 degree rotation
%C Column 2 of A187624
%e Some solutions for 4X4
%e ..1..2..0..2....2..2..0..2....1..1..2..1....1..2..1..1....2..0..1..2
%e ..0..2..1..2....0..2..2..2....2..1..1..1....1..1..1..2....1..2..2..0
%e ..1..2..1..0....2..2..2..0....1..1..1..2....2..1..1..1....0..2..2..1
%e ..1..0..1..2....2..0..2..2....1..2..1..1....1..1..2..1....2..1..0..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 12 2011