Mobius-like maps on irreducible polynomials and rational transformations

摘要

In the past few years, an action of the group PGL(2)(F-q) on the set of monic irreducible polynomials over F-q has been introduced and questions on the characterization and number of fixed points were discussed. In this paper we show that, in general, such fixed points arise from rational transformations, extending a work of Mattarei and Pizzato (2017). (C) 2019 Elsevier B.V. All rights reserved.