A208346 Number of n X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors)

1, 15, 1095, 230387, 191586797, 647640659639

Offset

1,2

Comments

Diagonal of A208353

Links

Table of n, a(n) for n=1..6.

Example

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

Crossrefs

Sequence in context: A203409 A207980 A131313 * A236329 A129764 A027552

Adjacent sequences: A208343 A208344 A208345 * A208347 A208348 A208349

Keyword

nonn

Author

R. H. Hardin Feb 25 2012

Status

approved