English

Generalized Wieferich primes and monogenic trinomials

Number Theory 2026-07-31 v1

Abstract

Let b2b\ge 2 be an integer and let p3p\ge 3 be a prime. We say that pp is a {\em generalized Wieferich prime base bb}, or more succinctly, a {\em base-bb Wieferich prime,} if bp11(modp2)b^{p-1}\equiv 1 \pmod{p^2}. When b=2b=2, pp is also known simply as a Wieferich prime. Let f(x)Z[x]f(x)\in {\mathbb Z}[x] be a monic polynomial of degree N2N\ge 2. We say that f(x)f(x) is monogenic if f(x)f(x) is irreducible over Q{\mathbb Q} and {1,θ,θ2,,θN1}\{1,\theta,\theta^2,\ldots,\theta^{N-1}\} is a basis for the ring of integers of Q(θ){\mathbb Q}(\theta), where f(θ)=0f(\theta)=0. Recently, the third author proved that x2p+2xp+2x^{2p}+2x^p+2 is monogenic if and only if pp is not a Wieferich prime. In this article, we generalize this result to x2n+bxn+bx^{2n}+bx^n+b with certain restrictions on b2b\ge 2 and n3n\ge 3.

Keywords

Cite

@article{arxiv.2607.29329,
  title  = {Generalized Wieferich primes and monogenic trinomials},
  author = {Amy Falk and Joshua Harrington and Lenny Jones},
  journal= {arXiv preprint arXiv:2607.29329},
  year   = {2026}
}