A221657 Number of 3Xn arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without move-in move-out left turns

0, 12, 230, 5879, 128076, 2853634, 63318470, 1408047450, 31296772948, 695652396949, 15461913567744, 343664536672236, 7638450184626910, 169775851711606490, 3773518891128106982, 83872027453458936923

Offset

1,2

Comments

Row 3 of A221655

Links

R. H. Hardin, Table of n, a(n) for n = 1..26

Example

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

Crossrefs

Sequence in context: A318417 A034832 A231448 * A089370 A171093 A089343

Adjacent sequences: A221654 A221655 A221656 * A221658 A221659 A221660

Keyword

nonn

Author

R. H. Hardin Jan 21 2013

Status

approved