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Units in Integral Group Rings for Order pq

Published online by Cambridge University Press:  20 November 2018

Klaus Hoechsmann*
Affiliation:
Department of Mathematics University of British Columbia Vancouver, British Columbia V6TJY4
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Abstract

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For any finite abelian group A, let Ω(A) denote the group of units in the integral group ring which are mapped to cyclotomic units by every character of A. It always contains a subgroup Y(A), of finite index, for which a basis can be systematically exhibited. For A of order pq, where p and q are odd primes, we derive estimates for the index [Ω(A) : Y(A)]. In particular, we obtain conditions for its triviality.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1995

References

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