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An algorithm for finding the Veech group of an origami

Gabriela Schmithuesen
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Abstract

We study the Veech group of an origami, i.e. of a translation surface, tessellated by parallelograms. We show that it is isomorphic to the image of a certain subgroup of Aut(F_2) in SL_2(Z) = Out^+(F_2). Based on this we present an algorithm that determines the Veech group.

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Gabriela Schmithuesen. 2004-01-15. An algorithm for finding the Veech group of an origami. https://arxiv.org/abs/math/0401185

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