On the number of solutions of two-variable diagonal quartic equations over finite fields

Let $p$ be a odd prime number and let $\mathbb{F}_q$ be the finite field of characteristic $p$ with $q$ elements. In this paper, by using the Gauss sum and Jacobi sum, we give an explicit formula for the number $N(x_1^4+x_2^4=c)$ of solutions of the following two-variable diagonal quartic equations...

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Bibliographic Details
Main Authors: Junyong Zhao, Yang Zhao, Yujun Niu
Format: Article
Language:English
Published: AIMS Press 2020-04-01
Series:AIMS Mathematics
Subjects:
Online Access:https://www.aimspress.com/article/10.3934/math.2020192/fulltext.html
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Summary:Let $p$ be a odd prime number and let $\mathbb{F}_q$ be the finite field of characteristic $p$ with $q$ elements. In this paper, by using the Gauss sum and Jacobi sum, we give an explicit formula for the number $N(x_1^4+x_2^4=c)$ of solutions of the following two-variable diagonal quartic equations over $\mathbb{F}_q$: $x_1^4+x_2^4=c$ with $c\in\mathbb{F}_q^*$. From this result, one can deduce that $N(x_1^4+x_2^4=c)=q+O(q^{\frac{1}{2}}).$
ISSN:2473-6988