Suppose that $a_n$ is a complex sequence such that $\limsup_{n \to \infty} |a_n|^{1/n} = L$ for some $L$. Then, I want to verify the claim:
$$ \limsup_{n \to \infty} n^{3/n}|a_n|^{1/n} = L$$
But, I am not so sure how to manipulate this sequence. How do I estimate the term $n^{1/n}?$