The Dot-Depth Hierarchy, 45 Years Later

@inproceedings{Pin2017TheDH,
  title={The Dot-Depth Hierarchy, 45 Years Later},
  author={Jean-{\'E}ric Pin},
  booktitle={The Role of Theory in Computer Science},
  year={2017}
}
  • J. Pin
  • Published in
    The Role of Theory in…
    2017
  • Computer Science
In 1970, R. S. Cohen and Janusz A. Brzozowski introduced a hierarchy of star-free languages called the dot-depth hierarchy. This hierarchy and its generalisations, together with the problems attached to them, had a long-lasting influence on the development of automata theory. This survey article reports on the numerous results and conjectures attached to this hierarchy. This paper is a follow-up of the survey article Open problems about regular languages, 35 years later [57]. The dot-depth… 

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