A221250 Number of n X n arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2

0, 4, 30, 58081, 78633756, 4919350997521, 720107530988047980, 2283974100099963226425600

Offset

1,2

Comments

Diagonal of A221255

Links

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

Example

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

Crossrefs

Sequence in context: A234566 A365366 A201974 * A119926 A103307 A196248

Adjacent sequences: A221247 A221248 A221249 * A221251 A221252 A221253

Keyword

nonn

Author

R. H. Hardin Jan 06 2013

Status

approved