A208471 Number of 6Xn nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

203, 4213597, 675203938944, 441285917587055633, 838683310903953794594668, 3787532222733253394267947322830

Offset: 1

Author

R. H. Hardin Feb 27 2012

Keywords

• nonn

Comments

Row 6 of A208466

Examples

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