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A209340 Number of n-bead necklaces labeled with numbers -4..4 allowing reversal, with sum zero with no three beads in a row equal. 0
1, 5, 12, 72, 400, 2698, 18646, 136000, 1013342, 7713270, 59569974, 465894736, 3681136600, 29342106638 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A209344.

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

Some solutions for n=7:

.-3...-3...-4...-4...-4...-4...-3...-4...-4...-3...-3...-4...-4...-3...-4...-4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A242043 A156236 A209481 * A128323 A202203 A074245

Adjacent sequences:  A209337 A209338 A209339 * A209341 A209342 A209343

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 06 2012

STATUS

approved

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Last modified August 3 13:49 EDT 2020. Contains 336198 sequences. (Running on oeis4.)