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arXiv · 1206.5876

Coordinates of R[x,y]: Constructions and classifications

Eric Edo
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Abstract

Let R be a PID. We construct and classify all coordinates of R[x,y] of the form p_2y+Q_2(p_1x+Q_1(y)) with p_1 and p_2 in qt(R) and Q_1 and Q_2 in qt(R)[y]. From this construction (with R=K[z]) we obtain non tame automorphisms s of K[x,y,z] (where K is a field of characteristic 0) such that the sub-group generated by s and the affine automorphisms contains all tame automorphisms.

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Eric Edo. 2012-06-26. Coordinates of R[x,y]: Constructions and classifications. https://arxiv.org/abs/1206.5876

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