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A209026
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Number of n-bead necklaces labeled with numbers -2..2 allowing reversal, with sum zero and first differences in -2..2.
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1
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1, 2, 2, 6, 11, 33, 86, 278, 873, 2938, 9904, 34321, 119673, 422725, 1502590, 5381671, 19377063, 70138385, 254978018, 930709334, 3409356533, 12530190100, 46188325542, 170723964752, 632624262841, 2349655631568, 8745690221340, 32617408075856
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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LINKS
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EXAMPLE
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Some solutions for n=6:
..0...-1...-1...-2...-2...-2...-1...-1...-2...-1...-1...-1...-2...-1...-1...-1
..0....0....0....0....0...-1...-1...-1...-1...-1...-1....0...-1...-1....0....0
..0....0....0....1....0....1....0....0....1...-1....1....1....1....0...-1....1
..0....1....0....0....1....0....0....0....2....1....0...-1....1....1....0...-1
..0...-1....0....1....1....2....1....2....1....1....0....0....1....0....2....1
..0....1....1....0....0....0....1....0...-1....1....1....1....0....1....0....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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EXTENSIONS
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STATUS
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approved
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