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A Dual Approach to Triangle Sequences: A Multidimensional Continued Fraction Algorithm

S. Assaf·L. Chen·T. Cheslack-Postava·B. Cooper·A. Diesl·T. Garrity·M. Lepinski·A. Schuyler
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Abstract

A dual approach to defining the triangle sequence (a type of multidimensional continued fraction algorithm, initially developed in NT/9906016) for a pair of real numbers is presented, providing a new, clean geometric interpretation of the triangle sequence. We give a new criterion for when a triangle sequence uniquely describes a pair of numbers and give the first explicit examples of triangle sequences that do not uniquely describe a pair of reals. Finally, this dual approach yields that the triangle sequence is topologically strongly mixing, meaning in particular that it is topologically ergodic.

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S. Assaf, L. Chen, T. Cheslack-Postava, B. Cooper, A. Diesl, T. Garrity, M. Lepinski, A. Schuyler. 2002-06-10. A Dual Approach to Triangle Sequences: A Multidimensional Continued Fraction Algorithm. https://arxiv.org/abs/math/0206105

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