2006/08/24 by Balkova, Lubomira, Pelantova, Edita, Steiner, Wolfgang · 1 citation
#Combinatorics (math.CO) #Discrete Mathematics (cs.DM) #FOS: Computer and information sciences #FOS: Mathematics
paper · doi:10.48550/arxiv.math/0608603
An infinite word has the property Rm if every factor has exactly m return words. Vuillon showed that R2 characterizes Sturmian words. We prove that a word satisfies Rm if its complexity function is (m-1)n+1 and if it contains no weak bispecial factor. These conditions are necessary for m=3, whereas for m=4 the complexity function need not be 3n+1. New examples of words satisfying Rm are given by words related to digital expansions in real bases.