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%I #17 Oct 07 2017 18:01:23
%S 1,2,3,5,6,2,8,9,3,11,14,15,5,6,18,6,20,21,23,8,26,10,9,29,30,12,33,
%T 11,35,36,15,39,41,16,14,44,18,15,18,48,50,51,6,53,54,18,56,22,24,20,
%U 63,21,65,27,68,69,23,30,28,74,75,30,78,26,33,81,10,83,86,29,89,90,30,36,40
%N phi(n)/tau(n), for odd squarefree n > 1 (A056911), phi = A000010, tau = A000005.
%H Ivan Neretin, <a href="/A094872/b094872.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000010(A056911(n+1)) / A000005(A056911(n+1)). - _Altug Alkan_, Oct 04 2017
%t EulerPhi[#]/DivisorSigma[0, #] & /@ Select[Range[3, 190, 2], SquareFreeQ] (* _Ivan Neretin_, Oct 04 2017 *)
%o (PARI) for(n=1,95,if(issquarefree(k=2*n+1),print1(eulerphi(k)/numdiv(k),","))) \\ _Klaus Brockhaus_, Jun 16 2004
%Y Cf. A056911.
%K nonn
%O 1,2
%A _Lekraj Beedassy_, Jun 16 2004
%E Corrected and extended by _Klaus Brockhaus_, Jun 16 2004
%E a(16)=6 corrected by _Ivan Neretin_, Oct 04 2017
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