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A078769 n.phi(n)^2<sigma(n)^2. 0

%I #2 Mar 31 2012 13:21:55

%S 2,3,4,6,8,10,12,14,18,20,24,30,36,42,48,60,84,90,120

%N n.phi(n)^2<sigma(n)^2.

%e 8*phi(8)^2=128, sigma(8)^2=225

%o (PARI) for (n=1,1000, if (eulerphi(n)^2*n<sigma(n)^2,print1(n",")))

%Y Cf. A064375.

%K nonn

%O 0,1

%A _Jon Perry_, Jan 09 2003

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Last modified July 23 20:21 EDT 2024. Contains 374553 sequences. (Running on oeis4.)