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arXiv · 1412.1726

Conway-Coxeter friezes and beyond: Polynomially weighted walks around dissected polygons and generalized frieze patterns

Abstract

Conway and Coxeter introduced frieze patterns in 1973 and classified them via triangulated polygons. The determinant of the matrix associated to a frieze table was computed explicitly by Broline, Crowe and Isaacs in 1974, a result generalized 2012 by Baur and Marsh in the context of cluster algebras of type A. Higher angulations of polygons and associated generalized frieze patterns were studied in a joint paper with Holm and Jørgensen. Here we take these results further; we allow arbitrary dissections and introduce polynomially weighted walks around such dissected polygons. The corresponding generalized frieze table satisfies a complementary symmetry condition; its determinant is a multisymmetric multivariate polynomial that is given explicitly. But even more, the frieze matrix may be transformed over a ring of Laurent polynomials to a nice diagonal form generalizing the Smith normal form result given in an earlier joint paper with Holm and Jørgensen. Considering the generalized polynomial frieze in this context it is also shown that the non-zero local determinants are monomials that are given explicitly, depending on the geometry of the dissected polygon.

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Christine Bessenrodt. 2014-12-04. Conway-Coxeter friezes and beyond: Polynomially weighted walks around dissected polygons and generalized frieze patterns. https://arxiv.org/abs/1412.1726

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