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A208940 Number of n-bead necklaces labeled with numbers -3..3 not allowing reversal, with sum zero with no three beads in a row equal. 0
1, 4, 12, 57, 274, 1464, 7974, 45050, 260046, 1529746, 9129838, 55159410, 336661016, 2072786142, 12858170994, 80288297320, 504231724034 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 3 of A208945.
LINKS
EXAMPLE
Some solutions for n=5:
.-2...-3...-3...-3...-3...-2...-3...-2...-2...-3...-3...-2...-3...-3...-2...-2
..1...-2....2....0....3....2....1....1...-2...-3....3...-2...-1...-1....0...-1
.-1....3....1....0...-2...-2....1....1....0....3...-3....2....3....3...-1....2
.-1....3...-1....3....2....3....2...-2....2....0....3....3....3...-2....2...-2
..3...-1....1....0....0...-1...-1....2....2....3....0...-1...-2....3....1....3
CROSSREFS
Sequence in context: A144012 A197924 A065125 * A209068 A177265 A243923
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 03 2012
STATUS
approved

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Last modified May 27 17:52 EDT 2024. Contains 372880 sequences. (Running on oeis4.)