A068351 - OEIS

%I #16 May 11 2023 18:33:54

%S 720,840,900,960,1008,1080,1200,1260,1320,1440,1512,1560,1584,1620,

%T 1680,1800,1848,1872,1890,1920,1980,2016,2040,2100,2160,2184,2280,

%U 2310,2340,2376,2400,2520,2640,2688,2700,2730,2760,2772,2808,2856,2880,2940

%N Numbers n such that n*tau(n)>prime(3*n) where tau(n)=A000005(n).

%C Only 13 of the first 2500 terms are odd, and each one of them is a multiple of 5. - _Harvey P. Dale_, Jun 15 2014

%H Harvey P. Dale, <a href="/A068351/b068351.txt">Table of n, a(n) for n = 1..2500</a>

%t Select[Range[3000],# DivisorSigma[0,#]>Prime[3#]&] (* _Harvey P. Dale_, Jun 15 2014 *)

%o (PARI) for(n=1,3300, if(n*numdiv(n)>prime(3*n),print1(n,",")))

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Feb 28 2002