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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).
1
6896, 1495040, 4653056000, 8403942375424, 20170789919653888, 42129429039341895680, 95229762257179140685824, 206324876650202359620698112, 458191976247070056511019417600
OFFSET
1,1
FORMULA
Empirical recurrence of order 47 (see link above).
EXAMPLE
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
CROSSREFS
Row 7 of A233174.
Sequence in context: A031761 A184791 A184787 * A233262 A233245 A233223
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 05 2013
STATUS
approved