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%I #22 Jun 17 2018 01:59:14
%S 5,119,3553,4147,8323,198679,218569,248501,298129,468809,547261,
%T 1098349,1398061,1947379,1990417,3076549,3453289,3994753,6969529,
%U 7690249,8790439,11905457,13097327,14346577,14732011,14988967,15286973,16145269,20851493,21622867,23083081,24924599,26218777,26326867
%N Numbers k such that 3*phi(k) = 2*sigma(k).
%H Jud McCranie, <a href="/A065818/b065818.txt">Table of n, a(n) for n = 1..10000</a> (first 75 terms from Harry J. Smith)
%e n = 3553, 3*phi(3553) = 8640 = 2*4320 = 2*sigma(3553).
%t Select[Range[20000000], 3EulerPhi[#] == 2DivisorSigma[1, #] &] (* _Harvey P. Dale_, Apr 18 2011 *)
%o (PARI) { n=0; for (m=1, 10^9, if (3*eulerphi(m) == 2*sigma(m), write("b065818.txt", n++, " ", m); if (n==75, return)) ) } \\ _Harry J. Smith_, Oct 31 2009
%Y Cf. A000010, A000203, A062699, A065819.
%K nonn
%O 1,1
%A _Labos Elemer_, Nov 23 2001
%E a(22)-a(28) from _Harry J. Smith_, Oct 31 2009
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