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Recurrence relation oddball one

  1. Sep 20, 2011 #1
    1. The problem statement, all variables and given/known data

    T(n) = 2T(n-1)

    3. The attempt at a solution

    I am trying to show the iterations.

    T(n) = 2T(n-1)
    T(n) = 22T(n-2)
    T(n) = 222T(n-3)

    Is this the right track? Where the result would be 22222....1eventually?

    The problem just feels awkward D:

    If my answer is right is there any way to get this into a summation form?
  2. jcsd
  3. Sep 21, 2011 #2
    Usually for these you start with a small n (or your base case) and start to look for a pattern.

    T(1) = x
    T(2) = x + something
    T(3) = x + T(2)
    T(n) = The summation of some pattern you found

    Give that a try instead of looking for a pattern at step n.
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