Jørgensen's inequality for classical Schottky groups of real type

Abstract

In this paper we consider Jørgensen's inequalities for classical Schottky groups of the real type. The infimum of Jørgensen's numbers for groups of types II, V and VII are 16, 4 $(1+\sqrt{2}{)}^2$ and 4 $(1+\sqrt{2}{)}^2$, respectively, each of which is the best possible for Jørgensen's inequality.