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%I #27 May 05 2023 08:41:14
%S 240,336,432,528,560,624,648,810,816,880,912,1040,1104,1134,1232,1360,
%T 1392,1456,1488,1520,1536,1776,1782,1840,1904,1968,2000,2064,2106,
%U 2128,2256,2288,2320,2480,2544,2560,2576,2754,2832,2835,2928
%N Numbers with 20 divisors.
%C Numbers of the form p^19, p*q^9 (A179692), p*q*r^4 (A179644) or p^3*q^4 (A179666), where p, q and r are distinct primes. - _R. J. Mathar_, Mar 01 2010
%H R. J. Mathar, <a href="/A030638/b030638.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[20000],DivisorSigma[0,#]==20&] (* _Vladimir Joseph Stephan Orlovsky_, May 05 2011 *)
%o (PARI) is(n)=numdiv(n)==20 \\ _Charles R Greathouse IV_, Jun 19 2016
%Y Cf. A030636, A030637, A137484.
%K nonn
%O 1,1
%A _Jeff Burch_
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