A221230 Number of nX2 arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, with no occupancy greater than 2

1, 14, 119, 852, 6360, 47334, 351402, 2609499, 19373481, 143810755, 1067445448, 7922843437, 58803820979, 436439347912, 3239207207387, 24040945903904, 178428089506023, 1324262997498462, 9828446743250451, 72944964878131496

Offset

1,2

Comments

Column 2 of A221234

Links

R. H. Hardin, Table of n, a(n) for n = 1..209

Formula

Empirical: a(n) = 13*a(n-1) -48*a(n-2) +60*a(n-3) -124*a(n-4) +370*a(n-5) -458*a(n-6) +370*a(n-7) -768*a(n-8) +889*a(n-9) -476*a(n-10) +126*a(n-11) -17*a(n-12) +a(n-13)

Example

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

Crossrefs

Sequence in context: A073383 A022642 A268446 * A240051 A202072 A280003

Adjacent sequences: A221227 A221228 A221229 * A221231 A221232 A221233

Keyword

nonn

Author

R. H. Hardin Jan 05 2013

Status

approved