login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Today, Nov 11 2014, is the 4th anniversary of the launch of the new OEIS web site. 70,000 sequences have been added in these four years, all edited by volunteers. Please make a donation (tax deductible in the US) to help keep the OEIS running.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A030634 Numbers with 16 divisors. 18
120, 168, 210, 216, 264, 270, 280, 312, 330, 378, 384, 390, 408, 440, 456, 462, 510, 520, 546, 552, 570, 594, 616, 640, 680, 690, 696, 702, 714, 728, 744, 750, 760, 770, 798, 858, 870, 888, 896, 910, 918, 920, 930, 945, 952, 966, 984, 1000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers of the form p^15 (subset of A010803), p*q^7, p*q*r^3 or p^3*q^3, or p*q*r*s, where p, q, r and s are distinct primes. [From R. J. Mathar, Mar 01 2010]

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[3000], DivisorSigma[0, #]==16&] (* Vladimir Joseph Stephan Orlovsky, May 05 2011 *)

CROSSREFS

Cf. A030631, A030632, A030633.

Sequence in context: A179642 A099832 A111399 * A189975 A232461 A090782

Adjacent sequences:  A030631 A030632 A030633 * A030635 A030636 A030637

KEYWORD

nonn

AUTHOR

Jeff Burch

STATUS

approved

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

Content is available under The OEIS End-User License Agreement .

Last modified November 24 10:51 EST 2014. Contains 249895 sequences.