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arXiv · 2603.01679

Bi-twisted conjugacy in finite groups

Pieter Senden·Sam Tertooy
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Abstract

We provide two alternative ways to determine the number of bi-twisted conjugacy classes in a finite group: one using irreducible characters and one using ordinary conjugacy classes. In addition, we show various equalities and (sharp) inequalities for Reidemeister numbers, as well as relations between bi-twisted conjugacy, representation theory, and fixed-point free automorphisms.

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Pieter Senden, Sam Tertooy. 2026-07-06. Bi-twisted conjugacy in finite groups. https://arxiv.org/abs/2603.01679

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