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phonic
Aug16-05, 05:39 AM
Dear members,

I am calculating the following limit:


\lim_{t\rightarrow \infty} \sum_{k=1}^{t-2} \frac{\lambda^{t-k-1}}{k}

where

0 < \lambda <1


Does any body know how to do it? Thanks a lot!

rachmaninoff
Aug16-05, 01:32 PM
A hint:

0\leq \lim_{t\rightarrow \infty} \sum_{k=1}^{t-2} \frac{\lambda^{t-k-1}}{k}=\lim_{t\rightarrow \infty} \lambda^t \sum_{k=1}^{t-2} \frac{\lambda^{k-1}}{k} \leq \lim_{t\rightarrow \infty} \lambda^t \sum_{k=1}^{\infty} \frac{\lambda^{k-1}}{k}