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arXiv · 0706.4184

Constructing (almost) rigid rings and a UFD having infinitely generated Derksen and Makar-Limanov invariant

David Finston·Stefan Maubach
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Abstract

An example is given of a UFD which has infinitely generated Derksen invariant. The ring is \textquotedblleft almost rigid\textquotedblright\ meaning that the Derksen invariant is equal to the Makar-Limanov invariant. Techniques to show that a ring is (almost) rigid are discussed, among which is a generalization of Mason's abc-theorem.

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David Finston, Stefan Maubach. 2007-06-28. Constructing (almost) rigid rings and a UFD having infinitely generated Derksen and Makar-Limanov invariant. https://arxiv.org/abs/0706.4184

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