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%I #10 Jun 24 2014 01:08:20
%S 181,899,2501,4687,10991,12989,17653,25199,25853,26549,26657,54473,
%T 65941,68381,72007,82777,96197,98903,102719,116449,124013,135907,
%U 150121,169153,188917,193553,201173,207461,219559,234301,237961,239279
%N Numbers n such that sigma(phi(n))/sigma(n) = 3.
%H Donovan Johnson, <a href="/A067383/b067383.txt">Table of n, a(n) for n = 1..1000</a>
%t For[ n=1, True, n++, If[ DivisorSigma[ 1, EulerPhi[ n ] ]/DivisorSigma[ 1, n ]==3, Print[ n ] ] ]
%o (PARI) is(n)=sigma(eulerphi(n=factor(n)))/sigma(n)==3 \\ _Charles R Greathouse IV_, Nov 27 2013
%Y Cf. A033631, A066831, A067382, A067384, A067385, A197952.
%K nonn
%O 1,1
%A _Dean Hickerson_, Jan 20 2002
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