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arXiv · 2604.17401

Markov fractions and Cohn matrices

A. P. Veselov
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Abstract

We show that the Markov fractions introduced recently by Springborn coincide with the index of the Cohn matrices defined by Aigner. This provides a simple concatenation rule for the corresponding continued fractions on the Conway topograph. We also discuss the $q$-deformation of Markov fractions in the sense of Morier-Genoud and Ovsienko, as well as their ``metallic" version motivated by the work of Spalding and the author.

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A. P. Veselov. 2026-04-19. Markov fractions and Cohn matrices. https://arxiv.org/abs/2604.17401

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