A221611 Number of 3Xn arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without move-in move-out left turns

0, 4, 54, 811, 11344, 160999, 2286878, 32522604, 462463456, 6575844726, 93499812718, 1329429617150, 18902457108916, 268763744810865, 3821403968991766, 54334437063306418, 772551392056456162

Offset

1,2

Comments

Row 3 of A221609

Links

R. H. Hardin, Table of n, a(n) for n = 1..56

Example

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

Crossrefs

Sequence in context: A294041 A055774 A071248 * A303048 A304556 A127833

Adjacent sequences: A221608 A221609 A221610 * A221612 A221613 A221614

Keyword

nonn

Author

R. H. Hardin Jan 20 2013

Status

approved