On Decidability of Intermediate Levels of Concatenation Hierarchies

• Type: Article in International Conference Proceedings Book
• Date: 2015

Authors

Almeida, J (Author) FCUP; Bartonova, J (Author) Other; Klima, O (Author) Other; Kunc, M (Author) Other

Conference proceedings International

Title: DEVELOPMENTS IN LANGUAGE THEORY (DLT 2015)

Pages: 58-70

19th International Conference on Developments in Language Theory (DLT)

Liverpool, ENGLAND, JUL 27-30, 2015

Indexing

ISI Web of Knowledge - 5 Citations

Scopus - 8 Citations

Other information

Authenticus ID: P-00G-SZ3

DOI: 10.1007/978-3-319-21500-6_4

Abstract (EN): It is proved that if definability of regular languages in the Sigma(n) fragment of the first-order logic on finite words is decidable, then it is decidable also for the Delta(n+1) fragment. In particular, the decidability for Delta(5) is obtained. More generally, for every concatenation hierarchy of regular languages, it is proved that decidability of one of its half levels implies decidability of the intersection of the following half level with its complement.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13