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arXiv · 2211.08011

Cluster Expansions: T-walks, Labeled Posets and Matrix Calculations

Ezgi Kantarcı Oğuz·Emine Yıldırım
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Abstract

We give two new combinatorial methods for computing cluster expansion formulas for arcs coming from possibly punctured surfaces. The first is by using $T$-walks, an extension of the $T$-path model for unpunctured surfaces to general surfaces. We also introduce a new way of generating $T$-paths. The second method is by using order ideals of labeled posets associated to arcs. We also use the theory of oriented posets to give a quick way to calculate the expressions using $2$ by $2$ matrices. The techniques introduced are applicable to different settings in cluster algebras and beyond.

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Ezgi Kantarcı Oğuz, Emine Yıldırım. 2024-02-21. Cluster Expansions: T-walks, Labeled Posets and Matrix Calculations. https://doi.org/10.1016/j.jalgebra.2025.01.024

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