Abstract
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.
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Câmpeanu, C., Salomaa, K. (2015). Nondeterministic Tree Width of Regular Languages. In: Shallit, J., Okhotin, A. (eds) Descriptional Complexity of Formal Systems. DCFS 2015. Lecture Notes in Computer Science(), vol 9118. Springer, Cham. https://doi.org/10.1007/978-3-319-19225-3_4
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DOI: https://doi.org/10.1007/978-3-319-19225-3_4
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