A194135 Number of ways to arrange 7 indistinguishable points on an n X n X n triangular grid so that no three points are collinear at any angle.

0, 0, 0, 0, 9, 1875, 52323, 695616, 5840088, 35715529, 172520643, 708871152, 2517687856, 8023634766, 23292994812, 62357664744, 155765126265, 367482996726, 822866800569, 1762214894004, 3621792301059

Offset: 1

Author

R. H. Hardin, Aug 17 2011

Keywords

• nonn

Comments

Column 7 of A194136.

Examples

			Some solutions for 5 X 5 X 5:
......0..........0..........0..........0..........0..........0..........0
.....0.1........1.0........1.0........0.1........0.1........1.0........1.1
....1.0.1......1.0.1......0.1.1......1.1.0......1.1.0......0.1.1......0.0.1
...1.0.1.0....0.1.0.1....1.0.0.1....1.0.0.1....0.0.1.1....1.1.0.0....1.1.0.0
..0.1.0.1.0..0.1.0.1.0..0.1.1.0.0..0.0.1.1.0..1.0.1.0.0..0.0.1.0.1..0.0.1.1.0