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A175743
Numbers with 33 divisors.
3
9216, 25600, 50176, 123904, 173056, 236196, 295936, 369664, 541696, 861184, 984064, 1401856, 1476225, 1721344, 1893376, 2262016, 2876416, 2893401, 3564544, 3810304, 4596736, 5161984, 5456896, 6390784, 7054336, 7144929, 8111104, 9634816, 9979281, 10445824
OFFSET
1,1
COMMENTS
Numbers of the form p^32 and p^10*q^2, where p and q are distinct primes.
FORMULA
A000005(a(n)) = 33.
Sum_{n>=1} 1/a(n) = P(2)*P(10) - P(12) + P(32) = 0.000203328..., where P is the prime zeta function. - Amiram Eldar, Jul 03 2022
MATHEMATICA
Select[Range[2000000], DivisorSigma[0, #]==33&] (* Harvey P. Dale, Jan 26 2011 *)
PROG
(PARI) is(n)=numdiv(n)==33 \\ Charles R Greathouse IV, Jun 19 2016
CROSSREFS
Cf. A000005.
Sequence in context: A234887 A251902 A234139 * A204103 A209595 A223303
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Aug 27 2010
EXTENSIONS
More terms from Harvey P. Dale, Jan 26 2011
Extended by T. D. Noe, May 08 2011
STATUS
approved