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On automorphisms of Danielewski surfaces

Anthony J. Crachiola
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Abstract

We develop techniques for computing the AK invariant of a domain with arbitrary characteristic. We use these techniques to describe for any field $K$ the automorphism group of $K[X,Y,Z]/(X^n Y - Z^2 - h(X)Z)$, where $h(0) \ne 0$ and $n \geq 2$, as well as the isomorphism classes of these algebras.

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Anthony J. Crachiola. 2004-06-21. On automorphisms of Danielewski surfaces. https://arxiv.org/abs/math/0406415

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