Orthogonal Concatenation: Language Equations and State Complexity.

Journal of Universal Computer Science 01/2010; 16:653-675. DOI: 10.3217/jucs-016-05-0653
Source: DBLP

ABSTRACT A language L is the orthogonal concatenation of languages L 1 and L 2 if every word of L can be written in a unique way as a concatenation of a word in L 1 and a word in L 2 . The notion can be generalized for arbitrary language operations. We consider decidability properties of language orthogonality and the solvability of language equations involving the orthogonal concatenation operation. We establish a tight bound for the state complexity of orthogonal concatenation of regular languages.

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