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%I #20 Aug 09 2021 20:25:45
%S 1,117,135,775,819,891,1521,1701,2325,3159,3375,4455,5733,6875,6975,
%T 10935,11907,19773,20625,20925,22113,22275,24025,40131,41067,43875,
%U 44375,49005,61875,62775,68607,72075,75625,83349,84375,85293
%N Odd numbers k that divide phi(k)*sigma(k).
%H Donovan Johnson, <a href="/A015706/b015706.txt">Table of n, a(n) for n = 1..3000</a>
%H Richard K. Guy, <a href="http://www.jstor.org/stable/2974586">Divisors and desires</a>, Amer. Math. Monthly, 104 (1997), 359-360.
%t Select[Range[1,85301,2],Divisible[EulerPhi[#]DivisorSigma[1,#],#]&] (* _Harvey P. Dale_, Aug 27 2013 *)
%o (PARI) isok(n) = (n%2) && !(sigma(n)*eulerphi(n) % n); \\ _Michel Marcus_, Oct 02 2017
%Y Cf. A011775.
%K nonn
%O 1,2
%A _Robert G. Wilson v_
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