A209070 Number of n-bead necklaces labeled with numbers -5..5 not allowing reversal, with sum zero and avoiding the pattern z z+1 z+2.

1, 6, 30, 223, 1722, 14431, 125428, 1125484, 10331019, 96583955, 916363757, 8801147754, 85402605777

Offset

1,2

Comments

Column 5 of A209073.

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for n=6:
.-3...-3...-5...-5...-3...-3...-5...-5...-5...-2...-4...-5...-4...-5...-3...-3
..3...-1....0....3....0....3....3...-4...-1....1...-1....0....2....3...-3...-2
.-2...-3....0....0...-3...-1....4....4....1....0....2....1....0...-4...-2....3
..0....5...-4...-1....2...-2....0....5....3....0....1....0...-2....0....4....2
.-1....3....4...-2...-1....5....2...-5....5...-2....5....5....5....3....5....1
..3...-1....5....5....5...-2...-4....5...-3....3...-3...-1...-1....3...-1...-1

Crossrefs

Sequence in context: A295497 A298457 A208942 * A259820 A126751 A009689

Adjacent sequences: A209067 A209068 A209069 * A209071 A209072 A209073

Keyword

nonn

Author

R. H. Hardin, Mar 04 2012

Status

approved