Rational functions of Degree Four that Permute the Projective Line over a Finite Field

Xiang-dong Hou

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arXiv · 2005.07213

Rational functions of Degree Four that Permute the Projective Line over a Finite Field

Xiang-dong Hou

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Abstract

Recently, rational functions of degree three that permute the projective line $\Bbb P^1(\Bbb F_q)$ over a finite field $ \Bbb F_q$ were determined by Ferraguti and Micheli. In the present paper, using a different method, we determine all rational functions of degree four that permute the $\Bbb P^1(\Bbb F_q)$.

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Xiang-dong Hou. 2020-05-14. Rational functions of Degree Four that Permute the Projective Line over a Finite Field. https://arxiv.org/abs/2005.07213

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