Date/heure
12 octobre 2023
14:30 - 15:30
Lieu
Salle Döblin
Oratrice ou orateur
Hajime Kaneko (Université de Tsukuba)
Catégorie d'évènement Séminaire de Théorie des Nombres de Nancy-Metz
Résumé
Lagrange spectrum is related to the rational approximations of badly approximable numbers. The discrete part of the spectrum is denoted in terms of Christoffel words. Multiplicative analogy of Lagrange spectrum was recently investigated, which is defined by rational approximations of geometric sequences and more general linear recurrence. Dubickas essentially found the relation of the discrete part of the multiplicative Lagrange spectrum and the limit sup words on the shift spaces with alternate order. Liao and Steiner found that such words are also related to the negative beta expansions. On this talk, we shall investigate limit sup words on more general ordered shift spaces. Such words are related to generalized beta expansion.
This is a joint work with Wolfgang Steiner.