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%I #31 Jan 30 2020 06:39:51
%S 39270,53130,71610,78540,82110,106260,108570,117810,122430,143220,
%T 157080,159390,164010,164220,212520,214830,217140,235620,244860,
%U 246330,247170,286440,293370,314160,318780,325710,328020,328440,353430,367290,425040,429660,434280
%N Numbers k such that Euler phi(Dedekind psi(k)) > k.
%C Counterexamples to a conjecture by Sandor.
%H Amiram Eldar, <a href="/A196200/b196200.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..66 from Indranil Ghosh)
%H Jozsef Sandor, <a href="http://www.emis.de/journals/JIPAM/article546.html?sid=546">On the Composition of Some Arithmetic Functions, II</a>, Journal of Inequalities in Pure and Applied Mathematics (JIPAM), Volume 6, Issue 3, Article 73, 2005.
%t Select[Range[39270, 434280], EulerPhi[# * Sum[MoebiusMu[d]^2 / d, {d, Divisors[#]}]] > # &] (* _Indranil Ghosh_, Mar 11 2017 *)
%o (PARI) a(m) = {for (n=1, m, if (eulerphi(n * sumdiv( n, d, moebius(d)^2 / d)) > n, print1(n, ", ")););}
%Y Cf. A000010, A001615.
%K nonn
%O 1,1
%A _Michel Marcus_, Dec 21 2012
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