Let $\alpha$ be an irationnalirrational number. Denote by $\mu(\alpha)$ its irationnalityirrationality measure?. Can one say anything about $\mu(\alpha^n)$ for every $n\in\mathbb N$?
Even more, one knows that $\mu(e)=2$. Can one say anything for $\mu(e^{p/q})$ for $\frac pq\in\mathbb Q^*$?