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A279287
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a(n) = numerator of (phi(n)/tau(n)).
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4
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1, 1, 1, 2, 2, 1, 3, 1, 2, 1, 5, 2, 6, 3, 2, 8, 8, 1, 9, 4, 3, 5, 11, 1, 20, 3, 9, 2, 14, 1, 15, 8, 5, 4, 6, 4, 18, 9, 6, 2, 20, 3, 21, 10, 4, 11, 23, 8, 14, 10, 8, 4, 26, 9, 10, 3, 9, 7, 29, 4, 30, 15, 6, 32, 12, 5, 33, 16, 11, 3, 35, 2, 36, 9, 20, 6, 15, 3
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OFFSET
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1,4
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COMMENTS
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See A279288 (denominator of (phi(n)/tau(n))) and A063070 (phi(n)-tau(n)).
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LINKS
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EXAMPLE
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For n = 6: phi(6)/tau(6) = 2/4 = 1/2; a(6) = 1.
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MAPLE
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MATHEMATICA
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Table[Numerator[EulerPhi[n]/DivisorSigma[0, n]], {n, 78}] (* Michael De Vlieger, Dec 09 2016 *)
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PROG
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(Magma) [Numerator(EulerPhi(n)/NumberOfDivisors(n)): n in[1..1000]]
(PARI) a(n) = numerator(eulerphi(n)/numdiv(n)) \\ Felix Fröhlich, Dec 09 2016
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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