A217267 Number of n X n arrays of occupancy after each element moves to some horizontal or vertical neighbor.

0, 9, 1472, 2572816, 48909857500, 10211121295308649, 23397344246732649325860

Offset

1,2

Comments

Diagonal of A217273

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Sequence in context: A120347 A230172 A231191 * A300594 A203649 A187131

Adjacent sequences: A217264 A217265 A217266 * A217268 A217269 A217270

Keyword

nonn,hard,more

Author

R. H. Hardin, Sep 29 2012

Status

approved