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 A030636 Numbers with 18 divisors. 10
 180, 252, 288, 300, 396, 450, 468, 588, 612, 684, 700, 768, 800, 828, 882, 972, 980, 1044, 1100, 1116, 1280, 1300, 1332, 1452, 1476, 1548, 1568, 1575, 1692, 1700, 1792, 1900, 1908, 2028, 2124, 2156, 2178, 2196, 2205, 2300, 2412, 2420, 2450 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers of the form p^17, p*q^8, p*q^2*r^2 or p^2*q^5, where p, q and r are distinct primes. - R. J. Mathar, Mar 01 2010 LINKS R. J. Mathar, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Range[2500], DivisorSigma[0, #]==18&]  (* Harvey P. Dale, Feb 01 2011 *) PROG (PARI) is(n)=numdiv(n)==18 \\ Charles R Greathouse IV, Jun 19 2016 CROSSREFS Cf. A030635 (17 divs), A030637 (19 divs). Sequence in context: A291457 A289056 A309380 * A179643 A160134 A135193 Adjacent sequences:  A030633 A030634 A030635 * A030637 A030638 A030639 KEYWORD nonn AUTHOR EXTENSIONS 882 inserted by N. J. A. Sloane, Mar 26 2007 STATUS approved

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Last modified October 21 03:24 EDT 2019. Contains 328291 sequences. (Running on oeis4.)