A187635 Number of 5X5 0..n arrays with the array of 2X2 subblock determinants antisymmetric under horizontal and vertical reflection and each non-centerline 2X2 subblock nonsingular.

954, 557382, 31903442, 686589106, 7836968262

Offset: 1

Author

R. H. Hardin Mar 12 2011

Keywords

• nonn

Comments

Row 4 of A187633

Examples

			Some n=3 solutions for 5X5
..2..0..2..1..2....2..0..2..1..2....2..0..2..3..2....2..0..2..0..2
..0..1..0..1..0....0..3..0..3..0....0..2..0..2..0....0..2..2..2..2
..1..2..3..1..1....3..0..2..0..3....2..2..1..1..2....3..0..1..0..3
..0..1..0..1..0....0..3..1..3..1....0..2..0..2..0....0..2..0..2..2
..2..1..2..0..2....2..3..3..3..3....2..0..2..3..2....2..0..2..1..3