A208297 Number of nX3 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal or antidiagonal neighbor (colorings ignoring permutations of colors).

2, 42, 2906, 433252, 113503692, 46538017584, 27700815674032, 22702140562948192, 24626774613248937584, 34296243004533645925408, 59839415643338575851475744, 128222446504879248765189962560, 331858429902640216546970620625280

Offset: 1

Author

R. H. Hardin Feb 25 2012

Keywords

• nonn

Comments

Column 3 of A208301

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..49