A221128 Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.

1, 987, 118472, 16436223, 2152770692, 282454178707, 36946896429843, 4831791752404317, 631836540867287034, 82621661239567004631

Offset: 1

Author

R. H. Hardin Jan 02 2013

Keywords

• nonn

Comments

Row 4 of A221125

Examples

			Some solutions for n=3
..0..1..0....1..2..1....2..1..0....1..1..0....1..2..1....0..2..1....1..2..0
..2..1..0....1..1..0....0..1..1....2..1..0....0..0..1....0..3..1....1..3..1
..3..1..0....2..0..0....3..2..0....3..1..1....3..1..2....0..1..1....0..0..1
..2..2..0....0..4..0....1..1..0....0..0..2....0..1..0....1..1..1....0..1..2