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 A209480 Number of n-bead necklaces labeled with numbers -3..3 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2. 0
 1, 4, 7, 35, 140, 731, 3740, 20888, 118137, 687981, 4059192, 24292229, 146840708, 895753665, 5505619880, 34065921090 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 3 of A209485. LINKS EXAMPLE Some solutions for n=8: .-3...-2...-3...-3...-3...-3...-3...-3...-3...-2...-3...-3...-3...-3...-3...-3 .-2...-2...-1...-1....0...-3....1....0...-1...-1...-2....0...-1...-1...-2...-3 ..0....0...-3....1...-1...-1...-1...-2....2...-2....0....3....2....0....1...-1 ..3....3....1....1....3...-1...-2....2....3...-1....1...-2....0...-3...-1....3 ..3...-2....2....1....2....3....1....3....1....3....3....2....2....2...-2....3 .-2....1....0....0....0....1....1....1....0....0....2....2....1...-1....3...-3 ..1....0....2....0...-3....2....2...-2...-3....0...-3...-3...-2....3....3....1 ..0....2....2....1....2....2....1....1....1....3....2....1....1....3....1....3 CROSSREFS Sequence in context: A140981 A283819 A124624 * A209339 A212500 A302198 Adjacent sequences:  A209477 A209478 A209479 * A209481 A209482 A209483 KEYWORD nonn AUTHOR R. H. Hardin, Mar 09 2012 STATUS approved

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Last modified December 2 12:01 EST 2021. Contains 349440 sequences. (Running on oeis4.)