English

Counting Irreducible polynomials with coefficients from thin subgroups

Number Theory 2026-01-21 v1

Abstract

L. Bary-Soroker and R. Shmueli (2026) have given an asymptotic formula for the number of irreducible polynomials over the finite fields Fq\mathbb F_q of qq elements, such that their coefficients are perfect squares in Fq\mathbb F_q and also extended this to classes of polynomials with coefficients described by finitely many unions of intersections of polynomial images. Here we use a different approach, which allows us to obtain another generalisation of this result to polynomials with coefficients from small subgroups of Fq\mathbb F_q^*. As a demonstration of the power of our approach, we also use it to count such irreducible polynomials with an additional condition, namely, with a prescribed value of their discriminant. This generalisation seems to be unachievable via the approach of L. Bary-Soroker and R. Shmueli (2026).

Keywords

Cite

@article{arxiv.2601.12968,
  title  = {Counting Irreducible polynomials with coefficients from thin subgroups},
  author = {Alina Ostafe and Igor E. Shparlinski},
  journal= {arXiv preprint arXiv:2601.12968},
  year   = {2026}
}
R2 v1 2026-07-01T09:10:27.762Z