A221485 Number of 3Xn arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction

0, 16, 50, 1407, 11784, 182524, 2017564, 26614749, 319184574, 4025795483, 49427052472, 615583634915, 7608564525014, 94422452015321, 1169266780165296, 14496003421951958, 179605335059387526, 2226026121739586735

Offset

1,2

Comments

Row 3 of A221483

Links

R. H. Hardin, Table of n, a(n) for n = 1..35

Example

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

Crossrefs

Sequence in context: A199809 A121863 A121864 * A204723 A204962 A080860

Adjacent sequences: A221482 A221483 A221484 * A221486 A221487 A221488

Keyword

nonn

Author

R. H. Hardin Jan 17 2013

Status

approved