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A172443
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Numbers with exactly 64 divisors.
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1
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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
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OFFSET
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1,1
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COMMENTS
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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
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LINKS
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David A. Corneth, Table of n, a(n) for n = 1..10000
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EXAMPLE
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10920 has 64 divisors.
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MATHEMATICA
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Select[Range[100000], DivisorSigma[0, #]==64&]
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PROG
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(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
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CROSSREFS
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Cf. A067885.
Sequence in context: A210171 A234987 A157322 * A190108 A308913 A145313
Adjacent sequences: A172440 A172441 A172442 * A172444 A172445 A172446
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KEYWORD
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nonn,easy
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AUTHOR
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Harvey P. Dale, Nov 20 2010
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STATUS
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approved
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