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arXiv · 0807.0124

Weyl groupoids of rank two and continued fractions

M. Cuntz·I. Heckenberger
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Abstract

A relationship between continued fractions and Weyl groupoids of Cartan schemes of rank two is found. This allows to decide easily if a given Cartan scheme of rank two admits a finite root system. We obtain obstructions and sharp bounds for the entries of the Cartan matrices. Key words: Cartan matrix, continued fraction, Nichols algebra, Weyl groupoid

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M. Cuntz, I. Heckenberger. 2008-07-01. Weyl groupoids of rank two and continued fractions. https://arxiv.org/abs/0807.0124

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