Possible Duplicate:
Compute $\liminf (a_k)^{1/k}$ $\limsup (a_k)^{1/k}$ $\liminf (a_{k+1}/a_k)$ and $\limsup (a_{k+1}/a_k)$ as $k \rightarrow \infty$
For the series $\frac{1}{2} + 1 + \frac{1}{8} + \frac{1}{4} + \frac{1}{32} + \frac{1}{16} + \frac{1}{128} + \frac{1}{64} +...$ Compute
$\liminf_{k\to\infty}(a_k)^{1/k}$
$\limsup_{k\to\infty}(a_k)^{1/k}$
$\liminf_{k\to\infty}(a_{k+1}/a_k)$ and
$\limsup_{k\to\infty}(a_{k+1}/a_k)$.
This is geometric series. But this does not order. So how I can find?