A221797 Number of nX4 arrays of occupancy after each element moves to some horizontal or vertical neighbor, without move-in move-out straight through or left turns

1, 39, 207, 3074, 26770, 308070, 3072428, 33022374, 341503872, 3603418695, 37628839684, 395070947793, 4136321868326, 43369462014426, 454388947033525, 4762556310357090, 49907461663171892, 523040952733010374

Offset

1,2

Comments

Column 4 of A221800

Links

R. H. Hardin, Table of n, a(n) for n = 1..48

Example

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

Crossrefs

Sequence in context: A243578 A124619 A290071 * A068975 A177709 A211503

Adjacent sequences: A221794 A221795 A221796 * A221798 A221799 A221800

Keyword

nonn

Author

R. H. Hardin Jan 26 2013

Status

approved