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A075034
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Numbers n such that tau(n) >= tau(n+1) >= tau(n+2) where tau(n) = number of divisors of n.
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4
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20, 21, 32, 33, 44, 45, 56, 57, 75, 80, 81, 84, 85, 92, 93, 104, 105, 116, 117, 132, 135, 140, 141, 144, 147, 165, 170, 171, 176, 177, 189, 200, 201, 204, 212, 213, 216, 217, 224, 225, 230, 231, 242, 243, 252, 260, 261, 272, 285, 296, 297, 300, 301, 315, 324
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OFFSET
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1,1
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LINKS
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Karl V. Keller, Jr., Table of n, a(n) for n = 1..10000
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MATHEMATICA
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nn = 400; t = DivisorSigma[0, Range[nn]]; Select[Range[nn-2], t[[#]] >= t[[#+1]] >= t[[#+2]] &] (* Harvey P. Dale, May 24 2012 *)
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PROG
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(Python)
from sympy import divisor_count as tau
[n for n in range(1, 333) if tau(n) >= tau(n+1) >= tau(n+2)] # Karl V. Keller, Jr., Jul 10 2020
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CROSSREFS
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Cf. A000005 (tau), A075032, A075033, A075035.
Sequence in context: A118865 A118608 A176241 * A022110 A041808 A041810
Adjacent sequences: A075031 A075032 A075033 * A075035 A075036 A075037
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy, Sep 02 2002
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EXTENSIONS
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More terms from Benoit Cloitre, Sep 07 2002
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STATUS
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approved
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