A221940 Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without move-in move-out straight through or left turns

1, 489, 24535, 1759041, 119035112, 8118923949, 552777330287, 37650441405451, 2564181255574899, 174635497977344862, 11893675692936218866, 810026663520753630706, 55167419097633745309553, 3757214394165203187203557

Offset

1,2

Comments

Row 4 of A221937

Links

R. H. Hardin, Table of n, a(n) for n = 1..24

Example

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

Crossrefs

Sequence in context: A214807 A251676 A230005 * A221739 A068751 A172951

Adjacent sequences: A221937 A221938 A221939 * A221941 A221942 A221943

Keyword

nonn

Author

R. H. Hardin Feb 01 2013

Status

approved