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A137493 Numbers with 30 divisors. 7
720, 1008, 1200, 1584, 1620, 1872, 2268, 2352, 2448, 2592, 2736, 2800, 3312, 3564, 3888, 3920, 4050, 4176, 4212, 4400, 4464, 4608, 5200, 5328, 5508, 5808, 5904, 6156, 6192, 6768, 6800, 7452, 7500, 7600, 7632, 7938, 8112, 8496, 8624, 8784, 9200, 9396 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Maple implementation: see A030513.

Numbers of the form p^29 (subset of A122970), p*q^2*r^4 (A179669), p^4*q^5 (A179702), p^2*q^9 (like 4608) or p*q^14, where p, q and r are distinct primes. - R. J. Mathar, Mar 01 2010

LINKS

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

FORMULA

A000005(a(n))=30.

MATHEMATICA

Select[Range[10000], DivisorSigma[0, #]==30&]  (* Harvey P. Dale, Feb 18 2011 *)

PROG

(PARI) is(n)=numdiv(n)==30 \\ Charles R Greathouse IV, Jun 19 2016

CROSSREFS

Cf. A137492 (29 divs), A139571 (31 divs).

Sequence in context: A068351 A067892 A257416 * A179669 A067808 A302127

Adjacent sequences:  A137490 A137491 A137492 * A137494 A137495 A137496

KEYWORD

nonn

AUTHOR

R. J. Mathar, Apr 22 2008

STATUS

approved

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Last modified October 19 04:04 EDT 2019. Contains 328211 sequences. (Running on oeis4.)