English

On planar functions over $\mathbb{F}_{q^3}$

Number Theory 2026-05-27 v1 Combinatorics

Abstract

Let Fq\mathbb{F}_q denote the finite field of order qq. For qq odd, we investigate the planarity over Fq3\mathbb{F}_{q^3} of the family fE,A,B,C,D(X):=EX2+AXq+1+BXq2+1+CX2q+DX2q2Fq[X]. f_{E,A,B,C,D}(X) := EX^2+ AX^{q+1}+ BX^{q^2+1}+CX^{2q} +DX^{2q^2}\in \mathbb{F}_{q}[X]. Using results from the theory of q-polynomials, we establish conditions under which these polynomials are planar functions. In particular, we provide characterizations for the planarity property and present new families of planar trinomials, quadrinomials, and pentanomials.

Keywords

Cite

@article{arxiv.2605.26263,
  title  = {On planar functions over $\mathbb{F}_{q^3}$},
  author = {João Paulo Guardieiro and Adler Marques and Luciane Quoos and Guilherme Tizziotti},
  journal= {arXiv preprint arXiv:2605.26263},
  year   = {2026}
}