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Invariants of the dihedral group D2p in characteristic two

Published online by Cambridge University Press:  19 October 2011

MARTIN KOHLS
Affiliation:
Technische Universität München, Zentrum Mathematik-M11, Boltzmannstrasse 3, 85748 Garching, Germany. e-mail: [email protected]
MÜFİT SEZER
Affiliation:
Department of Mathematics, Bilkent University, Ankara 06800Turkey. e-mail: [email protected]

Abstract

We consider finite dimensional representations of the dihedral group D2p over an algebraically closed field of characteristic two where p is an odd prime and study the degrees of generating and separating polynomials in the corresponding ring of invariants. We give an upper bound for the degrees of the polynomials in a minimal generating set that does not depend on p when the dimension of the representation is sufficiently large. We also show that p + 1 is the minimal number such that the invariants up to that degree always form a separating set. We also give an explicit description of a separating set.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2011

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References

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