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A209072 Number of n-bead necklaces labeled with numbers -7..7 not allowing reversal, with sum zero and avoiding the pattern z z+1 z+2. 0
1, 8, 56, 563, 6006, 68723, 817594, 10030238, 125899533, 1609360719, 20877938573, 274173012896 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 7 of A209073.

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

Some solutions for n=6:

.-7...-5...-7...-7...-7...-6...-7...-6...-5...-7...-5...-7...-6...-6...-6...-5

.-6....0....4....4...-6....3...-2....5....0....3...-3...-4....7...-2....5....5

..1...-4....6....2....4....6....3....5....4....2....6....2...-5....1...-4...-3

..1....3...-4....0....7....2....4....0....2....0....2....6....2....4....1....5

..4...-1...-2...-3....4...-4....0...-1...-3....1....1....5....4....5....3....0

..7....7....3....4...-2...-1....2...-3....2....1...-1...-2...-2...-2....1...-2

CROSSREFS

Sequence in context: A009107 A209665 A208944 * A133671 A326239 A154411

Adjacent sequences: A209069 A209070 A209071 * A209073 A209074 A209075

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 04 2012

STATUS

approved

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Last modified January 29 10:45 EST 2023. Contains 359921 sequences. (Running on oeis4.)