A233180 Number of 7Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabeled 6-colorings with no clashing color pairs).

6896, 1495040, 4653056000, 8403942375424, 20170789919653888, 42129429039341895680, 95229762257179140685824, 206324876650202359620698112, 458191976247070056511019417600

Offset: 1

Author

R. H. Hardin, Dec 05 2013

Keywords

• nonn

Examples

			Some solutions for n=2
..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
..0..2....2..1....5..2....2..1....0..2....0..2....2..1....0..4....0..4....2..1
..5..3....5..4....0..4....3..0....5..3....0..2....3..5....2..1....2..1....5..1
..1..3....2..1....2..4....3..4....5..1....5..1....3..4....3..5....3..4....2..1
..0..3....2..0....3..5....2..4....2..4....0..2....3..1....1..5....2..1....3..0
..0..2....2..4....1..0....0..1....0..1....5..3....5..4....4..5....3..5....4..5
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210
• R. H. Hardin, Huge empirical recurrence of order 47

Crossrefs

Row 7 of A233174.

Formula

Empirical recurrence of order 47 (see link above).