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A045677
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Number of 2n-bead balanced binary necklaces which are equivalent to their complement, but not equivalent to their reverse and their reversed complement.
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2
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0, 0, 0, 0, 0, 0, 2, 2, 8, 14, 36, 62, 142, 252, 524, 968, 1928, 3600, 7044, 13286, 25740, 48916, 94364, 180314, 347630, 666996, 1286712, 2477342, 4785824, 9240012, 17880320, 34604066, 67078024, 130085052, 252583200, 490722344, 954313264
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OFFSET
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0,7
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COMMENTS
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The number of 2n-bead balanced binary necklaces which are equivalent to their complement is A000013(n) and those which are equivalent to their reverse, complement and reversed complement is A045674(n). - Andrew Howroyd, Sep 28 2017
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LINKS
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FORMULA
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MATHEMATICA
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a[n_] := If[n == 0, 1, Sum[EulerPhi[2 d] 2^(n/d), {d, Divisors[n]}]/(2 n)] - A045674[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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