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A209001 Number of n-bead necklaces labeled with numbers -2..2 not allowing reversal, with sum zero and first and second differences in -2..2. 0
1, 1, 1, 3, 5, 10, 23, 66, 167, 445, 1171, 3167, 8569, 23618, 65589, 183955, 518183, 1467671, 4172881, 11913595, 34128769, 98093579, 282770735, 817397180, 2368770203 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
COMMENTS
Column 2 of A209007.
LINKS
EXAMPLE
All solutions for n=6:
.-1...-1...-1...-2...-2....0...-1...-1...-1...-1
..0...-1...-1...-1...-2....0....0...-1...-1....0
..0...-1....0....1....0....0....1....0....1....0
..1....1....0....2....2....0....0....1....1....0
..0....1....1....1....2....0....0....1....0....1
..0....1....1...-1....0....0....0....0....0....0
CROSSREFS
Sequence in context: A080522 A173232 A132332 * A240619 A171867 A243513
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 04 2012
STATUS
approved

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Last modified July 12 13:47 EDT 2024. Contains 374247 sequences. (Running on oeis4.)