1 problem

Let $f\in\mathcal{M}$. Suppose that … for some $\theta\in(0,1)$, and that there exists $c>0$ such that $|f(p^k)|^2=O(2^{k(1-c)})$ and $|f(p)|<1/c$ for all $k\geq 2$ and primes $p$.…