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A187669
Number of (n+1)X(n+1) 0..2 arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal
0
50, 550, 11282, 612204, 65533922, 18950885038
OFFSET
1,1
COMMENTS
Column 2 of A187670
EXAMPLE
Some solutions for 4X4
..1..0..1..2....2..0..2..1....1..1..2..0....2..2..2..2....1..0..1..0
..2..2..0..2....2..1..0..2....1..2..1..2....2..1..0..2....1..2..0..1
..1..0..1..2....2..0..1..1....2..1..2..1....2..0..1..2....1..0..2..1
..0..2..0..2....1..2..0..2....0..2..1..1....1..2..2..2....0..1..0..1
CROSSREFS
Sequence in context: A128954 A022147 A285044 * A366831 A160336 A231583
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 12 2011
STATUS
approved