Wilson's theorem states that a natural number $n > 1$ is a prime number if and only if the product of all the positive integers less than $n$ is one less than a multiple of $n$. Is there a version of the theorem in $\mathbb Z/p\mathbb Z[t]$ where $p$ is a prime? Are there any other non-trivial versions? My motivation is the following. There is no efficient algorithm for primes without Cramer's conjecture and so perhaps working with irreducible polynomials avoids **conjectures** and so is finding irreducibles in $\mathbb Z/p\mathbb Z[t]$ any easier?