A030630 - OEIS

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A030630

Numbers with 12 divisors.

60, 72, 84, 90, 96, 108, 126, 132, 140, 150, 156, 160, 198, 200, 204, 220, 224, 228, 234, 260, 276, 294, 306, 308, 315, 340, 342, 348, 350, 352, 364, 372, 380, 392, 414, 416, 444, 460, 476, 486, 490, 492, 495, 500, 516, 522, 525, 532, 544, 550

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OFFSET

1,1

COMMENTS

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

LINKS

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

MATHEMATICA

Select[Range[600], Length[Divisors[ # ]] == 12 &] (* Stefan Steinerberger, Apr 10 2006 *)

Select[Range[600], DivisorSigma[0, #]==12&] (* Harvey P. Dale, Jun 01 2016 *)

PROG

(PARI) for(n=1, 1e3, if(numdiv(n)==12, print1(n, ", "))) \\ Altug Alkan, Nov 11 2015

CROSSREFS

Sequence in context: A345997 A131564 A036457 * A068350 A265712 A376829

Adjacent sequences: A030627 A030628 A030629 * A030631 A030632 A030633

KEYWORD

nonn

AUTHOR

Jeff Burch

STATUS

approved