Two types of permutation polynomials with special forms

Dabin Zheng; Mu Yuan; Long Yu

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arXiv · 1805.10926

Two types of permutation polynomials with special forms

Dabin Zheng·Mu Yuan·Long Yu

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Abstract

Let $q$ be a power of a prime and $\mathbb{F}_q$ be a finite field with $q$ elements. In this paper, we propose four families of infinite classes of permutation trinomials having the form $cx-x^s + x^{qs}$ over $\mathbb{F}_{q^2}$, and investigate the relationship between this type of permutation polynomials with that of the form $(x^q-x+\delta)^s+cx$. Based on this relation, many classes of permutation trinomials having the form $(x^q-x+\delta)^s+cx$ without restriction on $\delta$ over $\mathbb{F}_{q^2}$ are derived from known permutation trinomials having the form $cx-x^s + x^{qs}$.

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Dabin Zheng, Mu Yuan, Long Yu. 2018-05-28. Two types of permutation polynomials with special forms. https://arxiv.org/abs/1805.10926

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