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Degree bounds for modular covariants

  • Jonathan Elmer ORCID logo EMAIL logo and Müfit Sezer
From the journal Forum Mathematicum


Let V,W be representations of a cyclic group G of prime order p over a field 𝕜 of characteristic p. The module of covariants 𝕜[V,W]G is the set of G-equivariant polynomial maps VW, and is a module over 𝕜[V]G. We give a formula for the Noether bound β(𝕜[V,W]G,𝕜[V]G), i.e. the minimal degree d such that 𝕜[V,W]G is generated over 𝕜[V]G by elements of degree at most d.

MSC 2010: 13A50

Communicated by Frederick R. Cohen

Funding statement: The second author is supported by a grant from TÜBITAK:119F181.


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Received: 2019-07-25
Revised: 2020-01-30
Published Online: 2020-03-20
Published in Print: 2020-07-01

© 2020 Walter de Gruyter GmbH, Berlin/Boston

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