A221786 Number of nX7 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns

0, 55, 840, 15936, 252538, 4781652, 76353254, 1402260000, 23429257696

Offset

1,2

Comments

Column 7 of A221787

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Sequence in context: A053138 A027784 A297523 * A358634 A241634 A008402

Adjacent sequences: A221783 A221784 A221785 * A221787 A221788 A221789

Keyword

nonn

Author

R. H. Hardin Jan 25 2013

Status

approved