The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A209339 Number of n-bead necklaces labeled with numbers -3..3 allowing reversal, with sum zero with no three beads in a row equal. 1
1, 4, 7, 35, 145, 770, 4029, 22739, 130282, 766177, 4566523, 27587850, 168340643, 1036444786, 6429150260, 40144480583 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 3 of A209344.
LINKS
EXAMPLE
Some solutions for n=8:
.-3...-3...-3...-3...-3...-3...-2...-3...-3...-3...-3...-3...-3...-3...-3...-3
..1....0...-2...-2....0....1....0....0...-1...-2...-1...-2....0....0...-2...-2
.-2...-1....1....1....0....1....2...-1...-2....2....0....2...-1....0...-2....0
..1....3....2....1...-3...-2...-1...-1....2....1....3....3...-2...-1....3....0
..0....0....2....0....1...-2....0....1....2....3....1....2....1....2....2....2
.-2....3...-2...-3....0....2....1...-2....0...-3...-2...-3....2....0....1...-1
..3...-3...-1....3....2....1...-2....3....0...-1....3....2....0....1....0....2
..2....1....3....3....3....2....2....3....2....3...-1...-1....3....1....1....2
CROSSREFS
Cf. A209344.
Sequence in context: A283819 A124624 A209480 * A212500 A302198 A279830
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 06 2012
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 8 17:25 EDT 2024. Contains 373224 sequences. (Running on oeis4.)