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Some Rings of Invariants that are Cohen-Macaulay

Published online by Cambridge University Press:  20 November 2018

Larry Smith*
Affiliation:
Mathematisches Institut, der Universität Göttingen, Bunsenstrasse 3-5, D 37073 Göttingen, Germany, e-mail:[email protected]
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Abstract

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Let be a representation of the finite group G over the field . If the order |G| of G is relatively prime to the characteristic of or n = 1 or 2, then it is known that the ring of invariants is Cohen-Macaulay. There are examples to show that need not be Cohen-Macaulay when |G| is divisible by the characteristic of . In all such examples is at least 4. In this note we fill the gap between these results and show that rings of invariants in three variables are always Cohen-Macaulay.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1996

References

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