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%I #25 Apr 17 2024 02:36:47
%S 720,864,1008,1080,1120,1260,1296,1440,1512,1584,1680,1728,1760,1800,
%T 1872,1980,2016,2080,2160,2240,2304,2376,2400,2448,2464,2520,2592,
%U 2640,2688,2700,2720,2736,2772,2800,2808,2835,2880,2912,3024,3080,3120,3168
%N Numbers k such that tau(k)*phi(k) > prime(k) where tau(k) = A000005(k).
%H Amiram Eldar, <a href="/A067892/b067892.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..3000 from Harvey P. Dale)
%t Select[Range[3200],EulerPhi[#]DivisorSigma[0,#]>Prime[#]&] (* _Harvey P. Dale_, Nov 17 2018 *)
%o (PARI) is(k) = numdiv(k) * eulerphi(k) > prime(k); \\ _Amiram Eldar_, Apr 17 2024
%o (PARI) lista(pmax) = {my(f, k = 0); forprime(p=1, pmax, k++; f = factor(k); if(numdiv(f) * eulerphi(f) > p, print1(k, ", ")));} \\ _Amiram Eldar_, Apr 17 2024
%Y Cf. A000005 (tau), A000010 (phi), A062355.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, Mar 02 2002