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%I #33 May 05 2023 09:47:55
%S 180,252,288,300,396,450,468,588,612,684,700,768,800,828,882,972,980,
%T 1044,1100,1116,1280,1300,1332,1452,1476,1548,1568,1575,1692,1700,
%U 1792,1900,1908,2028,2124,2156,2178,2196,2205,2300,2412,2420,2450
%N Numbers with 18 divisors.
%C Numbers of the form p^17, p*q^8 (A179668), p*q^2*r^2 (A179643) or p^2*q^5 (A179646), where p, q and r are distinct primes. - _R. J. Mathar_, Mar 01 2010
%H R. J. Mathar, <a href="/A030636/b030636.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[2500],DivisorSigma[0,#]==18&] (* _Harvey P. Dale_, Feb 01 2011 *)
%o (PARI) is(n)=numdiv(n)==18 \\ _Charles R Greathouse IV_, Jun 19 2016
%Y Cf. A030635 (17 divs), A030637 (19 divs).
%K nonn
%O 1,1
%A _Jeff Burch_
%E 882 inserted by _N. J. A. Sloane_, Mar 26 2007
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