A221885 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal, vertical or antidiagonal neighbor, without consecutive moves in the same direction.

13, 3223, 449069, 65039658, 9356131846, 1347142288446, 193944559610138, 27922276785982528, 4019968490456852781, 578754876292668561410, 83323335396986744374226, 11996060075504536682447230

Offset: 1

Author

R. H. Hardin Jan 30 2013

Keywords

• nonn

Comments

Column 4 of A221886

Examples

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