A216331 Number of horizontal and antidiagonal neighbor colorings of the even squares of an n X n array with new integer colors introduced in row major order.

1, 2, 15, 726, 2387180, 37060650272, 148049849072167133, 2765650089185458968363718

Offset: 1

Author

R. H. Hardin Sep 04 2012

Keywords

• nonn

Comments

Diagonal of A216338

Examples

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