A220999 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor

21, 2989, 394580, 51672851, 6758547145, 883809591160, 115571009291599, 15112491898694315, 1976162121051496204, 258409744432367037405, 33790541796768618273627, 4418566652828051992947794

Offset

1,1

Comments

Column 4 of A221001

Links

R. H. Hardin, Table of n, a(n) for n = 1..19

Example

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

Crossrefs

Sequence in context: A098375 A202793 A095154 * A231825 A347604 A222092

Adjacent sequences: A220996 A220997 A220998 * A221000 A221001 A221002

Keyword

nonn

Author

R. H. Hardin Dec 28 2012

Status

approved