Abstract
This note defines a family of Laurent polynomials indexed in \({\mathbb{P}^1\mathbb{Q}}\) which generalize the Markoff numbers and relate to the character variety of the one-cusped torus. We describe which monomials appear in each polynomial and prove all the coefficients are positive integers. We also conjecture a generalization of that positivity result.
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Guéritaud, F. Formal Markoff maps are positive. Geom Dedicata 134, 203–216 (2008). https://doi.org/10.1007/s10711-008-9256-y
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DOI: https://doi.org/10.1007/s10711-008-9256-y