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A208941
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Number of n-bead necklaces labeled with numbers -4..4 not allowing reversal, with sum zero with no three beads in a row equal.
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0
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1, 5, 20, 122, 766, 5238, 37044, 270832, 2024738, 15417296, 119124324, 931714740, 7362145488, 58683599062, 471302764880
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graph;
refs;
listen;
history;
text;
internal format)
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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=5:
.-2...-4...-4...-4...-3...-2...-4...-4...-2...-4...-2...-3...-3...-3...-4...-2
.-2....1....2....3....4....3....4....0...-2...-2...-2....0...-3....3...-1...-1
..0....2...-2...-2...-1....0...-1....3....0....3....1....2....0....0....2....3
..1....3....2....1....1...-1....2....2....2....0....1...-1....2...-1....0...-2
..3...-2....2....2...-1....0...-1...-1....2....3....2....2....4....1....3....2
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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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