A216691 Number of horizontal, vertical, diagonal or knight-move neighbor colorings of an nX2 array with new integer colors introduced in row major order

1, 2, 9, 90, 1451, 33694, 1047754, 41569451, 2033056870, 119455094071, 8265294573126, 662782941109746, 60794941081100523, 6309797655336714672

Offset

1,2

Comments

Column 2 of A216694

Links

Table of n, a(n) for n=1..14.

Example

Some solutions for n=4
..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
..1..2....2..3....2..3....1..2....2..3....1..2....2..3....2..3....2..3....2..3
..3..4....4..5....3..4....0..3....0..1....3..4....3..4....4..5....3..4....3..4
..1..5....6..7....4..5....3..2....4..3....1..0....0..1....6..1....5..6....5..1

Crossrefs

Sequence in context: A001192 A006120 A012941 * A059477 A136553 A266293

Adjacent sequences: A216688 A216689 A216690 * A216692 A216693 A216694

Keyword

nonn

Author

R. H. Hardin Sep 14 2012

Status

approved