Automatic sequences of rank two
Jason P. Bell, Jeffrey O. Shallit · RAIRO - Theoretical Informatics and Applications · 2022
Given a right-infinite word x over a finite alphabetA, therankof x is the size of the smallest setSof words overAsuch that x can be realized as an infinite concatenation of words inS. We show that the property of having rank two is decidable for the class ofk-automatic words for each integerk≥ 2.