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Register a new userCounting Coxeters friezes over a finite field via moduli spaces
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Authors
Sophie Morier-Genoud
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We count the number of Coxeters friezes over a finite field. Our method uses geometric realizations of the spaces of friezes in a certain completion of the classical moduli space $mathcal{M}_{0,n}$ allowing repeated points in the configurations. Counting points in the completed moduli space over a finite field is related to the enumeration problem of counting partitions of cyclically ordered set of points into subsets containing no consecutive points. In Appendix we provide an elementary solution for this enumeration problem.
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