A221322 Number of n X n arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2

1, 17, 2008, 2460824, 26135748494, 2568131772343102, 2242286238164144345340, 17596650117587793920907469032

Offset

1,2

Comments

Diagonal of A221328

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A276808 A088465 A001905 * A135505 A171704 A198288

Adjacent sequences: A221319 A221320 A221321 * A221323 A221324 A221325

Keyword

nonn

Author

R. H. Hardin Jan 11 2013

Status

approved