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arXiv · 2103.00664

Generalized cyclotomic mappings: Switching between polynomial, cyclotomic, and wreath product form

Alexander Bors·Qiang Wang
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Abstract

This paper is concerned with so-called index $d$ generalized cyclotomic mappings of a finite field $\mathbb{F}_q$, which are functions $\mathbb{F}_q\rightarrow\mathbb{F}_q$ that agree with a suitable monomial function $x\mapsto ax^r$ on each coset of the index $d$ subgroup of $\mathbb{F}_q^{\ast}$. We discuss two important rewriting procedures in the context of generalized cyclotomic mappings and present applications thereof that concern index $d$ generalized cyclotomic permutations of $\mathbb{F}_q$ and pertain to cycle structures, the classification of $(q-1)$-cycles and involutions, as well as inversion.

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Alexander Bors, Qiang Wang. 2021-03-01. Generalized cyclotomic mappings: Switching between polynomial, cyclotomic, and wreath product form. https://arxiv.org/abs/2103.00664

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