A215899 Number of diagonal and antidiagonal neighbor colorings of the even squares of an n X n array with new integer colors introduced in row major order.

1, 1, 15, 602, 2387217, 33093356640, 148049909203591059

Offset: 1

Author

R. H. Hardin Aug 26 2012

Keywords

• nonn

Comments

Diagonal of A215904

Examples

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