Minimal Union-Free Decompositions of Regular Languages
نویسندگان
چکیده
A regular language is called union-free if it can be represented by a regular expression that does not contain the union operation. Every regular language can be decomposed into a union of a finite number of union-free languages (the so-called union-free decomposition). We call the number of components in the minimal union-free decomposition of a regular language the union width of the regular language. In this paper we prove that union width of a regular language is computable and we present an algorithm for constructing a corresponding decomposition.
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