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Discrete Groups of Motions

Published online by Cambridge University Press:  20 November 2018

Leon Greenberg*
Affiliation:
Brown University
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This paper deals with the discrete groups of rigid motions of the hyperbolic plane. It is known (12) that the finitely generated, orientation-preserving groups have the following presentations:

Generators: .

Defining relations:

where km = ambmam-1bm-1. We shall denote this group by F(p; n1, … , nd; r).

In particular, the finitely generated free groups are contained among these. Indeed, one purpose of this paper is to indicate some geometrical methods for investigating free groups.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1960

References

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