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A056761
Odd numbers less than the cube of their number of divisors.
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
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
14175 = 81*25*7 has 30 divisors, and 30^3 = 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
KEYWORD
fini,full,nonn
AUTHOR
Labos Elemer, Aug 16 2000
STATUS
approved