A1 Refereed original research article in a scientific journal
Abelian bordered factors and periodicity
Authors: Charlier E, Harju T, Puzynina S, Zamboni LQ
Publisher: Academic Press LTD- Elsevier Science LTD
Publication year: 2016
Journal: European Journal of Combinatorics
Journal name in source: EUROPEAN JOURNAL OF COMBINATORICS
Journal acronym: Eur J Combin
Volume: 51
First page : 407
Last page: 418
Number of pages: 12
ISSN: 0195-6698
DOI: https://doi.org/10.1016/j.ejc.2015.07.003(external)
A finite word u is said to be bordered if u has a proper prefix which is also a suffix of u, and unbordered otherwise. Ehrenfeucht and Silberger proved that an infinite word is purely periodic if and only if it contains only finitely many unbordered factors. We are interested in abelian and weak abelian analogues of this result; namely, we investigate the following question(s): Let w be an infinite word such that all sufficiently long factors are (weakly) abelian bordered; is w (weakly) abelian periodic? In the process we answer a question of Avgustinovich et al. concerning the abelian critical factorization theorem. (C) 2015 Elsevier Ltd. All rights reserved.