Upper bounds for the level of normal subgroups of Hecke groups
Date
2011
Authors
Simos, T. E.
Journal Title
Journal ISSN
Volume Title
Publisher
Amer Inst Pyhsics
Abstract
In [4], Greenberg showed that n <= 6t(3) so that mu - nt <= 6t(4) for a normal subgroup N of level n and index mu having t parabolic classes in the modular group Gamma. Accola, [1], improved these to n <= 6t(2) always and n <= t(2) if Gamma/N is not abelian. In this work we generalise these results to Hecke groups. We get results between three parameters of a normal subgroup, i.e. the index mu, the level n and the parabolic class number t. We deal with the case q = 4, and then obtain the generalisation to other q. Two main problems here are the calculation of the number of normal subgroups and the determination of the bounds on the level n for a given t.
Description
Bu çalışma, 19-25 Eylül 2011 tarihleri arasında Halkidiki[Yunanistan]’da düzenlenen International Conference on Numerical Analysis and Applied Mathematics (ICNAAM)' da bildiri olarak sunulmuştur.
Keywords
Mathematics, Hecke groups, Level, Parabolic class number, Riemann surface, Automorphisms, Number
Citation
Demirci, M. vd. (2011). "Upper bounds for the level of normal subgroups of Hecke groups". ed. T. E. Simos. AIP Conference Proceedings, Numerical Analysis and Applied Mathematics Icnaam 2011: International Conference on Numerical Analysis and Applied Mathematics, 1389, 337-340.