A221509 Number of 3Xn arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without consecutive moves in the same direction

0, 64, 664, 31663, 730874, 22664752, 617892584, 17782943460, 499912745268, 14194927933912, 401323009766448, 11367289765226164, 321716709992052606, 9108319376609834007, 257833317722010551358, 7299063007433073641077

Offset

1,2

Comments

Row 3 of A221507

Links

Table of n, a(n) for n=1..16.

Example

Some solutions for n=3
..0..3..1....1..4..0....1..1..1....0..0..0....0..3..0....0..3..0....1..1..0
..0..3..2....0..1..2....0..1..1....1..2..2....0..0..2....2..3..1....2..4..0
..0..0..0....0..1..0....0..4..0....0..4..0....1..3..0....0..0..0....0..1..0

Crossrefs

Sequence in context: A297666 A269586 A269080 * A283337 A187620 A119287

Adjacent sequences: A221506 A221507 A221508 * A221510 A221511 A221512

Keyword

nonn

Author

R. H. Hardin Jan 18 2013

Status

approved