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Related papers: A cluster expansion formula ($A_n$ case)

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We give a uniform geometric realization for the cluster algebra of an arbitrary finite type with principal coefficients at an arbitrary acyclic seed. This algebra is realized as the coordinate ring of a certain reduced double Bruhat cell in…

Rings and Algebras · Mathematics 2008-05-19 Shih-Wei Yang , Andrei Zelevinsky

A cluster expansion is proposed, that applies to both continuous and discrete systems. The assumption for its convergence involves an extension of the neat Kotecky-Preiss criterion. Expressions and estimates for correlation functions are…

Mathematical Physics · Physics 2007-05-23 Daniel Ueltschi

We study super cluster algebra structure arising in examples provided by super Pl\"{u}cker and super Ptolemy relations. We develop the super cluster structure of the super Grassmannians $\Gr_{2|0}(n|1)$ for arbitrary $n$, which was…

Mathematical Physics · Physics 2025-06-23 Ekaterina Shemyakova

The Fomin-Zelevinsky Laurent phenomenon states that every cluster variable in a cluster algebra can be expressed as a Laurent polynomial in the variables lying in an arbitrary initial cluster. We give representation-theoretic formulas for…

Representation Theory · Mathematics 2020-12-21 Aslak Bakke Buan , Bethany Marsh

We present two simple descriptions of the denominator vectors of the cluster variables of a cluster algebra of finite type, with respect to any initial cluster seed: one in terms of the compatibility degrees between almost positive roots…

Combinatorics · Mathematics 2015-05-27 Cesar Ceballos , Vincent Pilaud

We continue our investigation on denominator conjecture of Fomin and Zelevinsky for cluster algebras via geometric models initialed in \cite{FG22}. In this paper, we confirm the denominator conjecture for cluster algebras of finite type.…

Representation Theory · Mathematics 2024-11-19 Changjian Fu , Shengfei Geng

For cluster algebras from surfaces, there is a known formula for cluster variables and F-polynomials in terms of the perfect matchings of snake graphs. If the cluster algebra has trivial coefficients, there is also a known formula for…

Combinatorics · Mathematics 2016-12-21 Michelle Rabideau

By viewing $\tilde{A}$ and $\tilde{D}$ type cluster algebras as triangulated surfaces, we find all cluster variables in terms of either (i) the frieze pattern (or bipartite belt) or (ii) the periodic quantities previously found for the…

Rings and Algebras · Mathematics 2021-05-26 Joe Pallister

Define an expansion poset to be the poset of monomials of a cluster variable attached to an arc in a polygon, where each monomial is represented by the corresponding combinatorial object from some fixed combinatorial cluster expansion…

Combinatorics · Mathematics 2020-05-06 Andrew Claussen

We provide multiple combinatorial expansion formulas - in terms of snake graphs, labelled posets, matrices, and $T$-walks - for elements in generalized cluster algebras associated to arcs on punctured orbifolds and illustrate their…

Combinatorics · Mathematics 2026-05-07 Esther Banaian , Wonwoo Kang , Elizabeth Kelley , Ezgi Kantarcı Oğuz , Emine Yıldırım

We study cluster algebras over $\mathbb{F}_2$. By the Laurent phenomenon there is a map from the set of seeds of the cluster algebra to the corresponding cluster variety. We show that in type $A$, fibers of this map can be described in…

Combinatorics · Mathematics 2025-09-08 Daniel Pérez Melesio , José Simental

Cluster algebras are commutative rings with a set of distinguished generators having a remarkable combinatorial structure. They were introduced by Fomin and Zelevinsky in 2000 in the context of Lie theory, but have since appeared in many…

Rings and Algebras · Mathematics 2013-03-19 Lauren K. Williams

In this paper, we prove some combinatorial results on generalized cluster algebras. To be more precisely, we prove that (i) the seeds of a generalized cluster algebra $\mathcal A(\mathcal S)$ whose clusters contain particular cluster…

Rings and Algebras · Mathematics 2019-10-09 Peigen Cao , Fang Li

In this note we explain how to obtain cluster algebras from triangulations of (punctured) discs following the approach of S. Fomin, M. Shapiro and D. Thurston. Furthermore, we give a description of m-cluster categories via diagonals (arcs)…

Combinatorics · Mathematics 2010-11-18 Karin Baur

The denominator conjecture, proposed by Fomin and Zelevinsky, says that for a cluster algebra, the cluster monomials are uniquely determined by their denominator vectors with respect to an initial cluster. In this paper, for a cluster…

Representation Theory · Mathematics 2024-07-17 Changjian Fu , Shengfei Geng

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…

Combinatorics · Mathematics 2025-04-08 Ezgi Kantarcı Oğuz , Emine Yıldırım

We formulate a general setting for the cluster expansion method and we discuss sufficient criteria for its convergence. We apply the results to systems of classical and quantum particles with stable interactions.

Mathematical Physics · Physics 2009-05-08 Suren Poghosyan , Daniel Ueltschi

It is conjectured by Ibrahim Assem, Ralf Schiffler and Vasilisa Shramchenko in "Cluster Automorphisms and Compatibility of Cluster Variables" that every cluster algebra is unistructural, that is to say, that the set of cluster variables…

Representation Theory · Mathematics 2016-02-22 Véronique Bazier-Matte

We characterize mutation-finite cluster algebras of rank at least 3 using positive semi-definite quadratic forms. In particular, we associate with every unpunctured bordered surface a positive semi-definite quadratic space $V$, and with…

Combinatorics · Mathematics 2021-01-22 Anna Felikson , John W. Lawson , Michael Shapiro , Pavel Tumarkin

We consider the quantum cluster algebras which are injective-reachable and introduce a triangular basis in every seed. We prove that, under some initial conditions, there exists a unique common triangular basis with respect to all seeds.…

Quantum Algebra · Mathematics 2017-10-18 Fan Qin