A221278 Number of 4Xn arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, with every occupancy equal to zero or two

0, 16, 16, 1089, 4920, 94864, 707600, 9517225, 87086136, 1018120464, 10150470672, 112064927121, 1158005545528, 12485339571600, 130957423363216

Offset

1,2

Comments

Row 4 of A221275

Links

Table of n, a(n) for n=1..15.

Example

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

Crossrefs

Sequence in context: A223820 A217980 A324023 * A239533 A070575 A004505

Adjacent sequences: A221275 A221276 A221277 * A221279 A221280 A221281

Keyword

nonn

Author

R. H. Hardin Jan 09 2013

Status

approved