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A060169
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Number of orbits of length n under the automorphism of the 3-torus whose periodic points are counted by A001945.
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8
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1, 0, 0, 1, 0, 1, 1, 0, 2, 1, 2, 2, 2, 4, 4, 5, 8, 6, 12, 13, 16, 23, 26, 35, 46, 54, 76, 89, 120, 154, 192, 255, 322, 411, 544, 679, 898, 1145, 1476, 1925, 2466, 3201, 4156, 5338, 6978, 8985
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OFFSET
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1,9
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COMMENTS
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The sequence A001945 records the number of points of period n under a map. The number of orbits of length n for this map gives the sequence above.
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LINKS
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FORMULA
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a(n) = (1/n)* Sum_{ d divides n } mu(d)*A001945(n/d).
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EXAMPLE
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u(17) = 8 since the map whose periodic points are counted by A001945 has 1 fixed point and 137 points of period 17, hence 8 orbits of length 7.
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CROSSREFS
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Cf. A001642, A060164, A060165, A060166, A060167, A060168, A060170, A060171, A060171, A060172, A060173.
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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