The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A030630 Numbers with 12 divisors. 15

%I #29 Aug 09 2019 04:35:30

%S 60,72,84,90,96,108,126,132,140,150,156,160,198,200,204,220,224,228,

%T 234,260,276,294,306,308,315,340,342,348,350,352,364,372,380,392,414,

%U 416,444,460,476,486,490,492,495,500,516,522,525,532,544,550

%N Numbers with 12 divisors.

%C Numbers of the form p^11 A079395, p*q^5 A178740, p*q*r^2 A085987, or p^2*q^3 A143610, where p, q and r are distinct primes. - _R. J. Mathar_, Mar 01 2010, Mar 17 2010

%H R. J. Mathar, <a href="/A030630/b030630.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[600], Length[Divisors[ # ]] == 12 &] (* _Stefan Steinerberger_, Apr 10 2006 *)

%t Select[Range[600],DivisorSigma[0,#]==12&] (* _Harvey P. Dale_, Jun 01 2016 *)

%o (PARI) for(n=1, 1e3, if(numdiv(n)==12, print1(n,", "))) \\ _Altug Alkan_, Nov 11 2015

%K nonn

%O 1,1

%A _Jeff Burch_

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 16 11:58 EDT 2024. Contains 372552 sequences. (Running on oeis4.)