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%I #17 Sep 08 2022 08:46:18
%S 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,
%T 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,
%U 1,1,1,1,1,1,3,1,1,1,1,5,5,1,1,1,1,2,1
%N a(n) = denominator of (phi(n)/tau(n)).
%C a(n) = denominator of (A000010(n)/A000005(n)).
%C See A279287 (numerator of (phi(n)/tau(n))) and A063070 (phi(n)-tau(n)).
%C a(n) = 1 and A279287(n) = 1 for numbers n in A020488; A279287(n) > a(n) for numbers n in A279289.
%H Jaroslav Krizek, <a href="/A279288/b279288.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 1 for numbers in A020491.
%e For n = 6: phi(6)/tau(6) = 2/4 = 1/2; a(6) = 2.
%t Table[Denominator[EulerPhi[n]/DivisorSigma[0, n]], {n, 120}] (* _Michael De Vlieger_, Dec 10 2016 *)
%o (Magma) [Denominator(EulerPhi(n)/NumberOfDivisors(n)): n in[1..1000]]
%o (PARI) a(n) = denominator(eulerphi(n)/numdiv(n)) \\ _Felix Fröhlich_, Dec 09 2016
%Y Cf. A000005, A000010, A020488, A020490, A020491, A063070, A279287, A279289.
%K nonn,frac
%O 1,2
%A _Jaroslav Krizek_, Dec 09 2016
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