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Numbers n such that n*tau(n) > omega(n)*prime(n) where tau(n) is the number of divisors of n and omega(n) the number of distinct prime factors of n.
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%I #11 Mar 16 2017 22:47:19

%S 1,2,3,4,8,9,16,24,27,32,36,48,64,72,96,108,128,144,160,180,192,216,

%T 240,256,288,320,324,360,384,400,432,480,504,512,540,576,600,640,648,

%U 672,720,756,768,792,800,840,864,896,900,936,960,972,1000,1008,1024

%N Numbers n such that n*tau(n) > omega(n)*prime(n) where tau(n) is the number of divisors of n and omega(n) the number of distinct prime factors of n.

%C There are very few odd terms in the sequence: 1, 3, 9, 27, 30375, 33075,...

%H Ivan Neretin, <a href="/A068317/b068317.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[1040], #*DivisorSigma[0, #] > PrimeNu[#]*Prime[#] &] (* _Ivan Neretin_, Mar 16 2017 *)

%o (PARI) for(n=1,1000, if(numdiv(n)*n>omega(n)*prime(n),print1(n,",")))

%K easy,nonn

%O 1,2

%A _Benoit Cloitre_, Feb 26 2002