The group of automorphisms of the function fields of the curve xn+ym+1=0
Kontogeorgis, Aristides I.
Abstract
We study the group of automorphisms of the function fields of the curves xn+ym−1=0 This group is bigger than
μ(m)×μ(n) in case m|n. If moreover n−1 is a power of the characteristic, then the group order exceeds the Hurwitz bound