Rings of invariants for modular representations of the Klein four group

Sezer, Müfit; Shank, R.

doi:10.1090/tran/6516

Rings of invariants for modular representations of the Klein four group
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by Müfit Sezer and R. James Shank PDF

Trans. Amer. Math. Soc. 368 (2016), 5655-5673 Request permission

Abstract:

We study the rings of invariants for the indecomposable modular representations of the Klein four group. For each such representation we compute the Noether number and give minimal generating sets for the Hilbert ideal and the field of fractions. We observe that, with the exception of the regular representation, the Hilbert ideal for each of these representations is a complete intersection.

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