A187703 Number of (n+1) X (n+1) 0..4 arrays with each 2 X 2 subblock off diagonal and antidiagonal nonsingular and the array of 2 X 2 subblock determinants antisymmetric about the diagonal and antidiagonal.

113, 31461, 1718, 875696, 4612

Offset: 1

Author

R. H. Hardin, Mar 12 2011

Keywords

• nonn

Comments

Column 4 of A187705.

Examples

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

Crossrefs

Cf. A187705.