Avoiding and Enforcing Repetitive Structures in Words 53 Erklärtes Ziel dieser Arbeit ist

Erklärtes Ziel dieser Arbeit ist es zum einen die Deregulierungspotentiale

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Der Anreiz

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Avoiding and Enforcing Repetitive Structures in Words 53 Erklärtes Ziel dieser Arbeit istAvoiding and enforcing repetitions in words are central topics in the area of combinatorics on words, with first results going back to the beginning of the 20th century. The results presented in this thesis extend and enrich the existing theory concerning the presence and absence of repetitive structures in words. In the first part the question whether such structures necessarily appear in infinite words over a finite alphabet is investigated. In