Erdős Problem 463 #
Reference: erdosproblems.com/463
Is there a function $f$ with $f(n)\to\infty$ as $n\to\infty$ such that, for all large $n$, there is a composite number $m$ such that $$ n + f(n) < m < n + p(m) $$ Here $p(m)$ is the least prime factor of $m$.