The Groups Generated by Maximal Sets of Symmetries of Riemann Surfaces and Extremal Quantities of their Ovals

Given g >= 2, there are formulas for the maximal number of non-conjugate symmetries of a Riemann surface of genus g and the maximal number of ovals for a given number of symmetries. Here we describe the algebraic structure of the automorphism groups of Riemann surfaces, supporting such extremal configurations of symmetries, showing that they are direct products of a dihedral group and some number of cyclic groups of order 2. This allows us to establish a deeper relation between the mentioned above quantitative (the number of symmetries) and qualitative (configurations of ovals) cases.