A221696 Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction.

1, 987, 63676, 7033429, 659020617, 64509677154, 6233675847228, 604346923784252, 58538232535028520, 5671250113728678882, 549411330594167686392, 53225495837252796349285, 5156336905625087231654148

Offset: 1

Author

R. H. Hardin Jan 22 2013

Keywords

• nonn

Comments

Row 4 of A221693

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..18