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A063469
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Numbers n such that tau(n)*3 = phi(n).
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9
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OFFSET
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1,1
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COMMENTS
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"phi(n)=k*Tau[n] has at most finitely many solutions for any constant k or even for slowly increasing functions like k(n)=n^(epsilon)." - Labos Elemer, Jul 20 2001
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LINKS
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MATHEMATICA
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Select[Range[300], 3DivisorSigma[0, #]==EulerPhi[#]&] (* Harvey P. Dale, Sep 15 2016 *)
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PROG
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(PARI) for(n=1, 10^7, if(3*numdiv(n)==eulerphi(n), print(n)))
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CROSSREFS
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KEYWORD
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fini,full,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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