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A208821
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Number of n-bead necklaces labeled with numbers -4..4 allowing reversal, with sum zero.
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0
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1, 5, 13, 75, 415, 2821, 19657, 144871, 1090645, 8392423, 65527045, 518173267, 4139803293, 33366946637
(list;
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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All solutions for n=3:
.-2...-1....0...-4...-2...-3...-3...-3...-1...-4...-2...-2...-4
.-1....0....0....1....0....0...-1....1...-1....0...-2....1....2
..3....1....0....3....2....3....4....2....2....4....4....1....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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