The repetition threshold introduced by Dejean and Brandenburg is the smallest real number α such that there exists an infinite word over a k-letter alphabet that avoids β-powers for all β > α. We extend this notion to colored graphs and obtain the value of the repetition thresholds of trees and “large enough” subdivisions of graphs for every alphabet size.
@article{ITA_2012__46_1_123_0, author = {Ochem, Pascal and Vaslet, Elise}, title = {Repetition thresholds for subdivided graphs and trees}, journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications}, volume = {46}, year = {2012}, pages = {123-130}, doi = {10.1051/ita/2011122}, mrnumber = {2904965}, zbl = {1247.68211}, language = {en}, url = {http://dml.mathdoc.fr/item/ITA_2012__46_1_123_0} }
Ochem, Pascal; Vaslet, Elise. Repetition thresholds for subdivided graphs and trees. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 46 (2012) pp. 123-130. doi : 10.1051/ita/2011122. http://gdmltest.u-ga.fr/item/ITA_2012__46_1_123_0/
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