PERMUTATION POLYNOMIALS ON Fq INDUCED FROM RÉDEI FUNCTION BIJECTIONS ON SUBGROUPS OF Fq

We construct classes of permutation polynomials over FQ2 by exhibiting classes of low-degree rational functions over FQ2 which induce bijections on the set of (Q + 1)-th roots of unity. As a consequence, we prove two conjectures about permutation trinomials from a recent paper by Tu, Zeng, Hu and Li.