# Abelian periods, partial words, and an extension of a theorem of Fine and Wilf

Francine Blanchet-Sadri; Sean Simmons; Amelia Tebbe; Amy Veprauskas

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications (2013)

- Volume: 47, Issue: 3, page 215-234
- ISSN: 0988-3754

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topBlanchet-Sadri, Francine, et al. "Abelian periods, partial words, and an extension of a theorem of Fine and Wilf." RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications 47.3 (2013): 215-234. <http://eudml.org/doc/273024>.

@article{Blanchet2013,

abstract = {Recently, Constantinescu and Ilie proved a variant of the well-known periodicity theorem of Fine and Wilf in the case of two relatively prime abelian periods and conjectured a result for the case of two non-relatively prime abelian periods. In this paper, we answer some open problems they suggested. We show that their conjecture is false but we give bounds, that depend on the two abelian periods, such that the conjecture is true for all words having length at least those bounds and show that some of them are optimal. We also extend their study to the context of partial words, giving optimal lengths and describing an algorithm for constructing optimal words.},

author = {Blanchet-Sadri, Francine, Simmons, Sean, Tebbe, Amelia, Veprauskas, Amy},

journal = {RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications},

keywords = {combinatorics on words; Fine and Wilf’s theorem; partial words; abelian periods; periods; optimal lengths; Fine-Wilf theorem; abelian periodicity; partial word; optimal length},

language = {eng},

number = {3},

pages = {215-234},

publisher = {EDP-Sciences},

title = {Abelian periods, partial words, and an extension of a theorem of Fine and Wilf},

url = {http://eudml.org/doc/273024},

volume = {47},

year = {2013},

}

TY - JOUR

AU - Blanchet-Sadri, Francine

AU - Simmons, Sean

AU - Tebbe, Amelia

AU - Veprauskas, Amy

TI - Abelian periods, partial words, and an extension of a theorem of Fine and Wilf

JO - RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

PY - 2013

PB - EDP-Sciences

VL - 47

IS - 3

SP - 215

EP - 234

AB - Recently, Constantinescu and Ilie proved a variant of the well-known periodicity theorem of Fine and Wilf in the case of two relatively prime abelian periods and conjectured a result for the case of two non-relatively prime abelian periods. In this paper, we answer some open problems they suggested. We show that their conjecture is false but we give bounds, that depend on the two abelian periods, such that the conjecture is true for all words having length at least those bounds and show that some of them are optimal. We also extend their study to the context of partial words, giving optimal lengths and describing an algorithm for constructing optimal words.

LA - eng

KW - combinatorics on words; Fine and Wilf’s theorem; partial words; abelian periods; periods; optimal lengths; Fine-Wilf theorem; abelian periodicity; partial word; optimal length

UR - http://eudml.org/doc/273024

ER -

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