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Search: id:A086565
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| A086565 |
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Smallest k such that (10^k - 1)/9 has n distinct prime divisors. Or a(n)= smallest value of k such that A000042(k) has exactly n distinct prime divisors. |
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+0
1
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| 1, 2, 3, 9, 8, 6, 15, 12, 18, 45, 24, 32, 54, 30, 42, 64, 102, 72, 108, 154, 60, 84, 96, 140, 126, 200, 120, 204
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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a(20) = 60; all other subsequent terms are > 70. - David Wasserman (wasserma(AT)spawar.navy.mil), Mar 28 2005
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CROSSREFS
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Cf. A000042.
Sequence in context: A016634 A021421 A152812 this_sequence A008291 A122665 A133066
Adjacent sequences: A086562 A086563 A086564 this_sequence A086566 A086567 A086568
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KEYWORD
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more,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 31 2003
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EXTENSIONS
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Corrected and extended by Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Sep 22 2003
a(12)-a(15) from David Wasserman (wasserma(AT)spawar.navy.mil), Mar 28 2005
a(16)-a(27) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 17 2008
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