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%I #20 May 05 2023 10:07:40
%S 960,1344,1728,2112,2240,2496,3264,3520,3648,4160,4416,4928,5440,5568,
%T 5824,5832,5952,6080,7104,7290,7360,7616,7872,8000,8256,8512,9024,
%U 9152,9280,9920,10176,10206,10304,11328,11712,11840,11968,12864,12992,13120
%N Numbers with 28 divisors.
%C Maple implementation: see A030513.
%C Numbers of the form p^27 (subset of A122968), p*q^13, p*q*r^6 (A179672) or p^3*q^6 (A179694), where p, q and r are distinct primes. - _R. J. Mathar_, Mar 01 2010
%H T. D. Noe, <a href="/A137491/b137491.txt">Table of n, a(n) for n = 1..1000</a>
%F A000005(a(n)) = 28.
%p with(numtheory): A137491:=n->`if`(tau(n)=28,n,NULL): seq(A137491(n), n=1..15000); # _Wesley Ivan Hurt_, Sep 18 2014
%t Select[Range[30000],DivisorSigma[0,#]==28&] (* _Vladimir Joseph Stephan Orlovsky_, May 06 2011 *)
%o (PARI) is(n)=numdiv(n)==28 \\ _Charles R Greathouse IV_, Jun 19 2016
%Y Cf. A030513-A030516, A030626, A030627, A030634-A030638, A005179, A003680, A096932, A061286, A061283.
%K nonn
%O 1,1
%A _R. J. Mathar_, Apr 22 2008
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