A221426 Number of n X 3 arrays of occupancy after each element moves to some horizontal or vertical neighbor, without consecutive moves in the same direction.

0, 42, 236, 4390, 46288, 622615, 7432234, 93888241, 1152556808, 14353368646, 177428523106, 2201695708298, 27265977663320, 338018668912390, 4188131487955190, 51907066789018822, 643229257269298586

Offset

1,2

Comments

Column 3 of A221429.

Links

R. H. Hardin, Table of n, a(n) for n = 1..58

Example

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

Crossrefs

Cf. A221429.

Sequence in context: A221523 A263304 A116004 * A122242 A046655 A299717

Adjacent sequences: A221423 A221424 A221425 * A221427 A221428 A221429

Keyword

nonn

Author

R. H. Hardin, Jan 15 2013

Status

approved