A207979 Number of n X 3 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).

5, 67, 4192, 587208, 147512732, 58668937932, 34119101220224, 27451586022436696, 29334574202437277520, 40343697156563884675488, 69646199705725564208484736, 147875840329637502384856552096, 379682313150983568999164195148800

Offset: 1

Author

R. H. Hardin, Feb 22 2012

Keywords

• nonn

Examples

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

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..190 (terms 1..16 from R. H. Hardin)

Crossrefs

Column 3 of A207981.