How to find average and power of a signal I need to find the average and the power of this signal:
$$x(n)=\sum_{k=1}^{\infty}2^{-k}e^{j2{\pi}kn}$$
The problem is that the summation starts at 1 and not at 0, and a part of that how can I find the average of a signal expressed in this way?
No solutions to homework problems, but here are two hints:

what is $e^{j2\pi nk}$ for integer $k$ and $n$?
do the values of $x[n]$ depend on $n$?