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A066315
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Number of aperiodic bracelets (or necklaces) with n red and blue beads such that the beads switch colors when bracelet is turned over.
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2
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1, 1, 3, 7, 20, 51, 154, 460, 1476, 4860, 16544, 57321, 202059, 720370, 2593470, 9408000, 34350506, 126108252, 465200332, 1723341185, 6408356052, 23911255544, 89495909408, 335916703284, 1264114452975, 4768464107355
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OFFSET
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1,3
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LINKS
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FORMULA
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MATHEMATICA
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a[n_] := Sum[MoebiusMu[n/d] A006080[d + 1], {d, Divisors[n]}];
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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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