A221820 Number of 4Xn arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without move-in move-out straight through or left turns

0, 40, 379, 29412, 854959, 35948127, 1290833232, 49447514716, 1844208808987, 69554410132666, 2610306743813999, 98167800387966673

Offset

1,2

Comments

Row 4 of A221817

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Sequence in context: A252180 A008355 A229716 * A301528 A253132 A293969

Adjacent sequences: A221817 A221818 A221819 * A221821 A221822 A221823

Keyword

nonn

Author

R. H. Hardin Jan 26 2013

Status

approved