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A056761 Odd numbers n such that the cube of the number of divisors of n is greater than n. 3
3, 5, 7, 9, 15, 21, 25, 27, 33, 35, 39, 45, 51, 55, 57, 63, 75, 81, 99, 105, 117, 135, 147, 153, 165, 171, 175, 189, 195, 207, 225, 231, 255, 273, 285, 297, 315, 345, 351, 357, 375, 385, 399, 405, 429, 435, 441, 455, 459, 465, 483, 495, 525, 567, 585, 675, 693 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Last term is a(267) = 883575, confirming the author's conjecture. [Charles R Greathouse IV, Apr 27 2011]

LINKS

Zak Seidov, Table of n, a(n) for n = 1..267 (complete sequence)

EXAMPLE

E.g. 14175=81*25*7 with 30 divisors and 27000>14175.

MATHEMATICA

Select[Range[1, 10^6 + 1, 2], DivisorSigma[0, #]^3 > # &] (* Michael De Vlieger, Oct 26 2017 *)

PROG

(PARI) isok(n) = (n % 2) && (numdiv(n)^3 > n); \\ Michel Marcus, Dec 19 2013

CROSSREFS

Cf. A035033-A035035, A034884, A000005, A000265, A056757-A056767, A056781.

Sequence in context: A109790 A290426 A211137 * A108347 A211128 A211129

Adjacent sequences:  A056758 A056759 A056760 * A056762 A056763 A056764

KEYWORD

fini,full,nonn

AUTHOR

Labos Elemer, Aug 16 2000

STATUS

approved

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Last modified January 19 15:53 EST 2019. Contains 319307 sequences. (Running on oeis4.)