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A137487 Numbers with 24 divisors. 2
360, 420, 480, 504, 540, 600, 630, 660, 672, 756, 780, 792, 864, 924, 936, 990, 1020, 1050, 1056, 1092, 1120, 1140, 1152, 1170, 1176, 1188, 1224, 1248, 1350, 1368, 1380, 1386, 1400, 1404, 1428, 1470, 1500, 1530, 1540, 1596, 1632, 1638, 1650, 1656, 1710 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Maple implementation: see A030513.

Numbers of the form p^23, p^2*q^7, p*q^2*r^3 (like 360, 504), p*q*r^5 (like 480, 672), p*q*r*s^2 (like 420, 660), p^3*q^5 (like 864) or p*q^11, where p, q, r and s are distinct primes. [From R. J. Mathar, Mar 01 2010]

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

FORMULA

A000005(a(n))=24.

MATHEMATICA

Select[Range[3000], DivisorSigma[0, #]==24&] (* Vladimir Joseph Stephan Orlovsky, May 05 2011 *)

CROSSREFS

Cf. A030513-A030516, A030626, A030627, A030634-A030638, A005179, A003680, A096932, A061286, A061283.

Sequence in context: A185641 A031966 A170830 * A069478 A060665 A072414

Adjacent sequences:  A137484 A137485 A137486 * A137488 A137489 A137490

KEYWORD

nonn

AUTHOR

R. J. Mathar, Apr 22 2008

STATUS

approved

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Last modified September 18 09:40 EDT 2014. Contains 246899 sequences.