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A209110
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Number of n-bead necklaces labeled with numbers -3..3 not allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.
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0
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1, 4, 11, 55, 261, 1373, 7377, 41256, 235639, 1372782, 8114465, 48564722, 293656843, 1791382922, 11011083783, 68131049950, 424018776003
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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Some solutions for n=6:
.-1...-3...-3...-1...-3...-2...-2...-3...-2...-3...-2...-2...-3...-3...-3...-3
.-1...-1...-3...-1....2...-1...-2....3....2...-2....0...-1...-2...-1....1....0
..0....2....2...-1....3....3....2...-2...-1....0....3....3....0....3....2...-2
..3....3....1....1...-2....0...-2....3....0....3....0...-1....2....2...-2....3
.-1....0....3...-1...-2....0....1....1....0...-1...-2....2....0...-1....3....2
..0...-1....0....3....2....0....3...-2....1....3....1...-1....3....0...-1....0
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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