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arXiv · 2104.12185

Primitive elements and $k$-th powers in finite fields

Hai-Liang Wu·Yue-Feng She
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Abstract

Let $\mathbb{F}_q$ be the finite field of $q$ elements, and let $k\mid q-1$ be a positive integer. Let $f(x)=ax^2+bx+c$ be a quadratic polynomial in $\mathbb{F}_q[x]$ with $b^2-4ac\ne0$. In this paper, we show that if $q>\max\{e^{e^3},(2k)^6\}$, then there is a primitive element $g$ of $\mathbb{F}_q$ such that $f(g)\in\mathbb{F}_q^{\times k}=\{x^k: x\in\mathbb{F}_q\setminus\{0\}\}$. Moreover, we shall confirm a conjecture posed by Sun.

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Hai-Liang Wu, Yue-Feng She. 2021-04-25. Primitive elements and $k$-th powers in finite fields. https://arxiv.org/abs/2104.12185

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