Recurrence relation oddball one

AI Thread Summary
The recurrence relation T(n) = 2T(n-1) with T(1) = 1 leads to a pattern where T(n) can be expressed as T(n) = 2^(n-1) * T(1). The iterative substitution shows that T(n) = 2^(n-1) * 1, simplifying to T(n) = 2^(n-1). To express this in summation form, one can analyze the pattern by starting from the base case and looking for a summation that captures the growth of T(n) based on previous terms. The discussion emphasizes the importance of identifying a clear pattern or formula for T(n) rather than just iterating through values. Ultimately, the solution can be derived through both iterative and summation approaches.
illidari
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Homework Statement



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

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?
 
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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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