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Involving Landau's 'big oh' notation

  1. Feb 7, 2012 #1

    Reb

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    (don't have an answer yet)

    We say that two sequences f,g are f=O(g) if-f there is a c>0 such that |f(n)|<c|g(n)| uniformly as n tends to infinity.

    If g(n)>2, does f=O(g) imply lnf=O(ln(g))?
     
  2. jcsd
  3. Feb 7, 2012 #2

    mathman

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    |f(n)| < c|g(n)| => ln(|f(n)|) < ln(c) + ln(|g(n)|). You should have |f(n)|, c > 1 to avoid problems with abs. value of logs.
     
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