A207981 T(n,k)=Number of n X k nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any diagonal or antidiagonal neighbor (colorings ignoring permutations of colors).

1, 2, 2, 5, 7, 5, 15, 67, 67, 15, 52, 1080, 4192, 1080, 52, 203, 25287, 587208, 587208, 25287, 203, 877, 794545, 147512732, 953124784, 147512732, 794545, 877, 4140, 31858034, 58668937932, 3410310590912, 3410310590912, 58668937932, 31858034

Offset: 1

Author

R. H. Hardin, Feb 22 2012

Keywords

• nonn
• tabl

Examples

			Table starts
....1........2...........5............15............52...............203
....2........7..........67..........1080.........25287............794545
....5.......67........4192........587208.....147512732.......58668937932
...15.....1080......587208.....953124784.3410310590912.22727131144960768
...52....25287...147512732.3410310590912
..203...794545.58668937932
..877.31858034
.4140
...
Some solutions for n=4 k=3
..0..0..0....0..0..1....0..0..0....0..0..0....0..1..0....0..0..0....0..0..0
..1..1..1....1..2..1....1..1..1....1..1..1....2..1..0....1..2..1....1..1..1
..2..0..2....1..2..0....0..0..2....0..0..0....0..1..3....0..0..0....2..2..0
..1..0..1....0..2..0....1..1..1....1..1..1....0..4..0....2..1..1....0..1..0
		

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..496 (terms 1..40 from R. H. Hardin).

Crossrefs

Columns 1..4 are A000110, A207978, A207979, A207980.

Main diagonal is A361452.

Cf. A207868.