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A060217
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Number of orbits of length n under the full 14-shift (whose periodic points are counted by A001023).
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1
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14, 91, 910, 9555, 107562, 1254435, 15059070, 184468830, 2295671560, 28925411697, 368142288150, 4724492067295, 61054982558010, 793714765724595, 10371206370484778, 136122083520848880, 1793608631137129170, 23715491899442676060, 314542313628890231430, 4183412771249777343369
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OFFSET
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1,1
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COMMENTS
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Number of Lyndon words (aperiodic necklaces) with n beads of 14 colors. - Andrew Howroyd, Dec 10 2017
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LINKS
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FORMULA
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a(n) = (1/n)* Sum_{d|n} mu(d)*A001023(n/d).
G.f.: Sum_{k>=1} mu(k)*log(1/(1 - 14*x^k))/k. - Ilya Gutkovskiy, May 19 2019
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EXAMPLE
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a(2)=91 since there are 196 points of period 2 in the full 14-shift and 14 fixed points, so there must be (196-14)/2 = 91 orbits of length 2.
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PROG
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(PARI) a001023(n) = 14^n;
a(n) = (1/n)*sumdiv(n, d, moebius(d)*a001023(n/d)); \\ Michel Marcus, Sep 11 2017
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CROSSREFS
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KEYWORD
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easy,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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