A221423 Number of 5 X n arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, with every occupancy equal to zero or two.

0, 32, 0, 13794, 0, 5501288, 0, 2238166260, 0, 896266172750, 0, 356943936626267, 0, 141932444866235538, 0, 56407987494575281915, 0, 22414489809013612468416, 0, 8906243419860155512004653

Offset

1,2

Links

Table of n, a(n) for n=1..20.

Example

Some solutions for n=4
..2..0..0..2....2..0..0..2....2..0..2..0....0..2..0..2....2..0..2..0
..0..2..2..2....2..0..0..2....2..2..2..0....2..0..0..2....2..0..0..2
..0..2..2..0....2..2..0..0....0..2..2..0....2..0..0..2....2..0..0..0
..0..0..0..2....0..2..2..2....0..0..2..0....2..0..0..0....2..2..2..0
..2..0..0..2....0..0..2..0....2..0..0..2....2..0..2..2....2..0..0..2

Crossrefs

Row 5 of A221419.

Sequence in context: A240253 A057376 A079312 * A062543 A086820 A354946

Adjacent sequences: A221420 A221421 A221422 * A221424 A221425 A221426

Keyword

nonn

Author

R. H. Hardin, Jan 15 2013

Status

approved