A187530 Number of 4X4 0..n arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under 90 degree rotation

104, 3790, 35026, 220802, 727842, 2327574, 5366230, 13768228, 28531154, 54987216, 90945478

Offset

1,1

Comments

Row 3 of A187528

Links

Table of n, a(n) for n=1..11.

Example

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

Crossrefs

Sequence in context: A217773 A298460 A299553 * A185741 A299333 A007267

Adjacent sequences: A187527 A187528 A187529 * A187531 A187532 A187533

Keyword

nonn

Author

R. H. Hardin Mar 10 2011

Status

approved