2 problems

Let $f\in\mathbb{Q}[X]$ have degree greater than $1$, and let $a\in\mathbb{Q}$. Write $\pi_{f,a}$ for the density, when it exists, of primes modulo which the iterates…

Let $K$ be a number field and let $f\in K[X]$ be a postcritically infinite polynomial, meaning that the forward orbit of at least one critical point of $f$ is infinite. Let the sta…