login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A208812
Number of n-bead necklaces labeled with numbers -6..6 not allowing reversal, with sum zero and three times sum of squares <= n*(6)*(6+1).
0
1, 4, 29, 236, 2095, 20409, 209793, 2220143, 23933783, 264637987, 2967244283, 33695174581, 387241027611
OFFSET
1,2
COMMENTS
Column 6 of A208814:
EXAMPLE
Some solutions for n=6:
.-3...-2...-5...-4...-4...-5...-4...-4...-6...-5...-6...-4...-5...-4...-5...-5
.-1...-2....3...-3....5....0...-4...-1....0....4....0...-1....3....4....0....1
.-1....3...-2...-2....3....1....2....1....3...-1....1...-4...-2...-1...-2....5
.-2...-2....0....5...-3....0....1...-1...-3...-4....6....3....4...-3....6...-4
..6...-2....0...-1...-1....2....4....1....5....1....1....4...-3....4....0...-1
..1....5....4....5....0....2....1....4....1....5...-2....2....3....0....1....4
CROSSREFS
Sequence in context: A140526 A151343 A371743 * A291103 A125808 A379875
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 01 2012
STATUS
approved