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A279288
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a(n) = denominator of (phi(n)/tau(n)).
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4
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1, 2, 1, 3, 1, 2, 1, 1, 1, 1, 1, 3, 1, 2, 1, 5, 1, 1, 1, 3, 1, 2, 1, 1, 3, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 3, 1, 2, 1, 1, 1, 2, 1, 3, 1, 2, 1, 5, 1, 3, 1, 1, 1, 4, 1, 1, 1, 1, 1, 3, 1, 2, 1, 7, 1, 2, 1, 3, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 5, 5, 1, 1, 1, 1, 2, 1
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OFFSET
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1,2
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COMMENTS
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See A279287 (numerator of (phi(n)/tau(n))) and A063070 (phi(n)-tau(n)).
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LINKS
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FORMULA
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EXAMPLE
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For n = 6: phi(6)/tau(6) = 2/4 = 1/2; a(6) = 2.
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MATHEMATICA
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Table[Denominator[EulerPhi[n]/DivisorSigma[0, n]], {n, 120}] (* Michael De Vlieger, Dec 10 2016 *)
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PROG
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(Magma) [Denominator(EulerPhi(n)/NumberOfDivisors(n)): n in[1..1000]]
(PARI) a(n) = denominator(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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