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A165497
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a(n) starts arithmetic progression of n terms separated by tau(a(n)), each term having the same number of divisors
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2
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1, 3, 3, 60, 60, 201, 481, 5989, 3122037, 4434429, 13576837, 183894465, 187925171, 209072257, 1498642520, 12239200420, 20220712468, 20220712468
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OFFSET
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1,2
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COMMENTS
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a(15) > 1e9
a(19) > 10^11. [From Donovan Johnson, Sep 24 2009]
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LINKS
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Table of n, a(n) for n=1..18.
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EXAMPLE
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tau(60) = tau(72) = tau(84) = tau(96) = tau(108) = 12. This is the first such progression of length greater than 3, so a(4) and a(5) are both 60.
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CROSSREFS
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Cf. A064491, A165498, A165499
Sequence in context: A225208 A100065 A066807 * A051752 A102065 A102074
Adjacent sequences: A165494 A165495 A165496 * A165498 A165499 A165500
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KEYWORD
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hard,nonn,more
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AUTHOR
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Hugo van der Sanden, Sep 21 2009
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EXTENSIONS
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a(15)-a(18) from Donovan Johnson, Sep 24 2009
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STATUS
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approved
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