A187632 Number of (n+1)X(n+1) 0..4 arrays with the array of 2X2 subblock determinants antisymmetric under horizontal and vertical reflection and each non-centerline 2X2 subblock nonsingular.

113, 12104, 106892, 686589106, 795758912

Offset: 1

Author

R. H. Hardin Mar 12 2011

Keywords

• nonn

Comments

Column 4 of A187633

Examples

			Some solutions for 4X4
..3..1..3..0....0..4..4..4....0..4..3..2....0..2..4..0....1..4..4..4
..3..0..0..1....1..0..0..1....3..0..0..4....2..0..0..1....1..0..0..1
..1..0..0..3....2..0..0..1....4..0..0..3....1..0..0..2....4..0..0..1
..3..3..1..0....1..2..4..0....2..3..4..2....2..4..2..0....4..1..4..3