A187697 Number of (n+1)X(n+1) 0..2 arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under horizontal and vertical reflection.

50, 8, 7954, 1548, 15128848, 454640, 231192094416

Offset: 1

Author

R. H. Hardin Mar 12 2011

Keywords

• nonn

Comments

Column 2 of A187699

Examples

			Some solutions for 4X4
..0..2..0..2....2..0..2..0....2..2..0..2....1..2..1..0....1..2..0..2
..1..1..1..1....1..2..0..2....1..0..1..0....0..1..0..1....2..2..1..2
..0..1..0..1....2..0..2..0....0..2..0..2....1..0..1..0....1..2..0..2
..2..1..2..0....1..2..1..2....1..0..1..0....0..1..2..1....2..2..1..0