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 A086564 Smallest k such that 10^k + 1 has n distinct prime divisors. 0
 0, 4, 3, 11, 9, 36, 15, 33, 39, 69, 63, 45, 171, 117, 243, 105, 150, 135, 165, 255, 231, 210 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS There are no further terms below 289. LINKS FORMULA a(n) = Log to the base 10 of {A086563(n)-1}. EXAMPLE a(5) = 9 = Log to the base 10 {1000000001 - 1}. CROSSREFS Cf. A086563. Sequence in context: A346614 A005013 A241643 * A316966 A295727 A200073 Adjacent sequences:  A086561 A086562 A086563 * A086565 A086566 A086567 KEYWORD more,nonn AUTHOR Amarnath Murthy, Aug 31 2003 EXTENSIONS More terms from Sascha Kurz, Sep 22 2003 a(10)-a(12) from David Wasserman, Mar 28 2005 a(13)-a(22) from Max Alekseyev, Apr 27 2010 STATUS approved

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Last modified December 7 15:24 EST 2021. Contains 349581 sequences. (Running on oeis4.)