Nondeterministic Tree Width of Regular Languages

  • Cezar Câmpeanu
  • Kai Salomaa
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9118)


The tree width of a nondeterministic finite automaton (NFA) counts the maximum number of computations the automaton may have on a given input. Here we consider the tree width of a regular language, which, roughly speaking, measures the amount of nondeterminism that a state-minimal NFA for the language needs. We prove that an infinite tree width is obtained from finite tree width, for most operations on regular languages.


Regular languages Nondeterministic finite automata Measures of nondeterminism 


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of Computer Science and Information TechnologyUniversity of Prince Edward IslandCharlottetownCanada
  2. 2.School of ComputingQueen’s UniversityKingstonCanada

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