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A209069 Number of n-bead necklaces labeled with numbers -4..4 not allowing reversal, with sum zero and avoiding the pattern z z+1 z+2. 0
1, 5, 20, 122, 766, 5239, 37108, 271732, 2035161, 15526728, 120213839, 942210714, 7461093141, 59602526850, 479745735803 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A209073.

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Some solutions for n=6:

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

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

.-1...-2....1...-1...-2....2...-1...-2....3....0....2...-1....3....2...-1....2

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

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

..0....3...-2...-3....0....4....0....3...-2....3...-2....2....4...-3....2....0

CROSSREFS

Sequence in context: A332710 A054720 A208941 * A301952 A110373 A081067

Adjacent sequences:  A209066 A209067 A209068 * A209070 A209071 A209072

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 04 2012

STATUS

approved

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Last modified December 3 22:32 EST 2021. Contains 349468 sequences. (Running on oeis4.)