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A172443
Numbers with exactly 64 divisors.
1
7560, 9240, 10920, 11880, 13440, 14040, 14280, 15960, 16632, 17160, 17280, 18360, 19320, 19656, 20520, 20790, 21000, 21120, 22440, 24024, 24192, 24360, 24570, 24840, 24960, 25080, 25704, 26040, 26520, 27000, 28728, 29568, 29640, 30030, 30360, 30888, 31080
OFFSET
1,1
COMMENTS
The first squarefree term of this sequence is the primorial a(34) = 30030.
Almost all terms of this sequence (in the sense of having relative density 1) are squarefree, that is in our case, the product of six distinct primes = A067885. - Charles R Greathouse IV, Aug 27 2021
LINKS
EXAMPLE
10920 has 64 divisors.
MATHEMATICA
Select[Range[100000], DivisorSigma[0, #]==64&]
PROG
(PARI) is(n) = numdiv(n) == 64 \\ David A. Corneth, Aug 27 2021
(Python)
from sympy import divisor_count
def ok(n): return divisor_count(n) == 64
print(list(filter(ok, range(31100)))) # Michael S. Branicky, Aug 27 2021
CROSSREFS
Cf. A067885.
Sequence in context: A210171 A234987 A157322 * A374788 A190108 A308913
KEYWORD
nonn,easy
AUTHOR
Harvey P. Dale, Nov 20 2010
STATUS
approved