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arXiv · 2605.31333

Degree shifts between q-deformed friezes and q-Farey labelings for general triangulations

Manabu Inuma·Ren Motomiya·Takeyoshi Kogiso
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Abstract

Morier-Genoud and Ovsienko introduced q-deformations of continued fractions, Farey labelings, and Conway--Coxeter friezes, and established relationships among them in restricted settings associated with triangulations having exactly two exterior cells. In this paper, we extend these correspondences to arbitrary subsequences of quiddities arising from general triangulations. We show that the numerator and denominator polynomials of q-deformed continued fractions coincide with entries of q-deformed Conway--Coxeter friezes, while the corresponding polynomials in q-Farey labelings agree with them up to explicit powers of q. These powers are described combinatorially in terms of the number of diagonals in the triangulation, or equivalently, the number of entries equal to 1 in the associated frieze. Furthermore, we determine the minimum and maximum degrees of these polynomials in terms of the same combinatorial data.

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Manabu Inuma, Ren Motomiya, Takeyoshi Kogiso. 2026-05-29. Degree shifts between q-deformed friezes and q-Farey labelings for general triangulations. https://arxiv.org/abs/2605.31333

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