m at h . A G ] 2 8 Ju n 20 07 Constructing ( almost ) rigid rings and a UFD having infinitely generated Derksen and Makar - Limanov invariant
نویسنده
چکیده
An example is given of a UFD which has infinitely generated Derksen invariant. The ring is “almost rigid” 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. AMS classification: 14R20, 13A50, 13N15.
منابع مشابه
Infinitely Generated Derksen and Makar-limanov Invariant *
In this paper, we give an example of a finitely generated 3-dimensional C-algebra which has infinitely generated Derksen invariant as well as MakarLimaonv invariant.
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