Title
On Decidability Of Intermediate Levels Of Concatenation Hierarchies
Abstract
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.
Year
DOI
Venue
2015
10.1007/978-3-319-21500-6_4
DEVELOPMENTS IN LANGUAGE THEORY (DLT 2015)
Field
DocType
Volume
Discrete mathematics,Combinatorics,Binary relation,Decidability,Concatenation,Sigma,Regular language,Membership problem,Transitive closure,Hierarchy,Mathematics
Conference
9168
ISSN
Citations 
PageRank 
0302-9743
9
0.82
References 
Authors
7
4
Name
Order
Citations
PageRank
J. Almeida16115.24
Jana Bartonová290.82
Ondrej Klíma3399.16
Michal Kunc413812.83