Characterizing Level One in Group-Based Concatenation Hierarchies

نویسندگان

چکیده

We investigate two operators on classes of regular languages: polynomial closure ( $$Pol$$ ) and Boolean $$Bool$$ ). apply these to group languages $$\mathcal {G}$$ their well-suited extensions {G} ^+$$ , which is the least algebra containing $$ $$\{\varepsilon \}$$ . This yields $$Bool(Pol(\mathcal {G}))$$ ^+))$$ These form first level in important classifications languages, called concatenation hierarchies, admit natural logical characterizations. present generic algebraic characterizations classes. They imply that one may decide whether a language belongs such class, provided more general problem separation decidable for input class The proofs are constructive rely exclusively notions from automata theory.

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ژورنال

عنوان ژورنال: Lecture Notes in Computer Science

سال: 2022

ISSN: ['1611-3349', '0302-9743']

DOI: https://doi.org/10.1007/978-3-031-09574-0_20