A221382 Number of 4Xn arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with every occupancy equal to zero or two

0, 1, 4, 25, 189, 1156, 6996, 43681, 268632, 1664100, 10278914, 63568729, 392903168, 2429109796

Offset

1,3

Comments

Row 4 of A221381

Links

Table of n, a(n) for n=1..14.

Example

All solutions for n=3
..0..2..0....0..2..2....0..2..2....0..2..0
..2..2..0....0..2..0....0..2..0....2..2..0
..0..2..0....0..2..0....0..2..2....0..2..2
..2..2..0....2..2..0....0..2..0....0..2..0

Crossrefs

Sequence in context: A054368 A365764 A135147 * A215791 A175913 A239996

Adjacent sequences: A221379 A221380 A221381 * A221383 A221384 A221385

Keyword

nonn

Author

R. H. Hardin Jan 14 2013

Status

approved