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Page 2887 of Mathematical Reviews Vol. , Issue 80G [page]

1980 Mathematical Reviews  
S. 80g:94065 Characterizing the regular prefix codes and right power-bounded languages. Inform. Process. Lett. 9 (1979), no. 1, 5-7.  ...  From the text: “We characterize the finite automata for the regu- lar right power-bounded languages by means of a simple proof which gives a decomposition into a finite union of prefix codes.  ... 

Page 6990 of Mathematical Reviews Vol. , Issue 96k [page]

1996 Mathematical Reviews  
In particular, using finite nilpotent monoids, we give a new characterization of finite maximal prefix, bifix and outfix codes.”  ...  First we determine the structure of cohesive prefix codes and then we study several relationships between maximal infix codes and maximal cohesive prefix codes.  ... 

On the Commutative Equivalence of Context-Free Languages [chapter]

Arturo Carpi, Flavio D'Alessandro
2018 Lecture Notes in Computer Science  
The problem of the commutative equivalence of context-free and regular languages is studied.  ...  In particular conditions ensuring that a context-free language of exponential growth is commutatively equivalent with a regular language are investigated.  ...  Thus one may ask whether any finite code Y has a power Y n which is commutatively prefix.  ... 
doi:10.1007/978-3-319-98654-8_14 fatcat:hb6ogniuebdixmenxvkmor6d64

Page 1616 of Mathematical Reviews Vol. 56, Issue 5 [page]

1978 Mathematical Reviews  
It is 12161 shown that a language is regular and right power-bounded if and | only if it is a finite union of regular prefix codes.” xT  ...  Regular prefix codes and right power-bounded languages. Semigroup Forum 13 (1976/77), no. 1, 77-83. Author’s summary: “‘Let X be a finite alphabet and let X* be the free monoid generated by X.  ... 

SD-Regular Transducer Expressions for Aperiodic Transformations

Luc Dartois, Paul Gastin, Shankara Narayanan Krishna
2021 2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)  
An SDRTE is a regular expression where Kleene stars are used in a restricted way: they can appear only on aperiodic languages which are prefix codes of bounded synchronization delay.  ...  Our result also generalizes a lesser known characterization by Sch ützenberger of aperiodic languages by SD-regular expressions (SD=AP).  ...  An SD prefix code is a prefix code with a bounded synchronisation delay. As an example, consider the prefix code C = {aa, ba} and the word ba(aa) d ∈ C * .  ... 
doi:10.1109/lics52264.2021.9470738 fatcat:2sl5e2ei2zbhxgwtlpv7za3hz4

Church-Rosser Systems, Codes with Bounded Synchronization Delay and Local Rees Extensions [chapter]

Volker Diekert, Lukas Fleischer
2017 Lecture Notes in Computer Science  
What is the common link, if there is any, between Church-Rosser systems, prefix codes with bounded synchronization delay, and local Rees extensions?  ...  a basis of a free submonoid in the free monoid of all words (over a given alphabet) and local Rees extensions provide structural insight into regular languages over words.  ...  In particular, it would be interesting to see whether there is a natural language characterization of Ap M H that relies on prefix codes with bounded synchronization delay.  ... 
doi:10.1007/978-3-319-66396-8_2 fatcat:d3aqsypoerdjla2tbqeyfvlkx4

Page 4315 of Mathematical Reviews Vol. , Issue 88h [page]

1988 Mathematical Reviews  
If the language generated by a polynomially bounded DOL system does not contain the null string then the language is either a prefix code or suffix code.  ...  Every infinite context-free DOL language is either a prefix code or a suffix code.”  ... 

Codes, languages and MOL schemes

H. J. Shyr, G. Thierrin
1977 RAIRO Informatique théorique  
The CODES, LANGUAGES AND MOL SCHEMES 299language A = {b n a\n^ 1} is a, regular right power-bounded language, but h (A) = { h (b)) n | n ^ 1 } is not a right power-bounded language, a contradiction.  ...  The language A = {b n a\n^\}isa regular right power-bounded language, but h (A) = { (vu) n v | n ^ 1 } = { v (uv) n \ n ^ 1 } is not a right powerbounded language, a contradiction. # The converse of this  ...  Since /z is injective, then h(A) n h (À) = 0, and therefore x nm x* n h(A) = 0. It follows then that h (A) is a power-separating language of order nm. #  ... 
doi:10.1051/ita/1977110402931 fatcat:boi2m5buyjgxtmntiszy3ja4vm

Cerny-like problems for finite sets of words

Arturo Carpi, Flavio D'Alessandro
2014 Italian Conference on Theoretical Computer Science  
In this theoretical setting, we investigate the problem of finding upper bounds to the minimal length of synchronizing and incompletable words of a finite language X in terms of the length of the words  ...  This paper situates itself in the theory of variable length codes and of finite automata where the concepts of completeness and synchronization play a central role.  ...  Let X be a prefix code of A * and suppose that X is a regular language.  ... 
dblp:conf/ictcs/CarpiD14 fatcat:oh3r5n3fuzbmlcpacmbwixrqxa

A new approach to formal language theory by kolmogorov complexity [chapter]

Ming Li, Paul M. B. Vitanyi
1989 Lecture Notes in Computer Science  
We give an alternative for pumping lemma(s) and a new characterization for regular languages.  ...  For the separation of deterministic contextfree languages and contextfrcc languages no pumping lemmas or any other general method was known.  ...  We thank Peter van Emde Boas, Theo Jansen, and Tao Jiang for reading and commenting on the manuscript. Tao Jiang also has suggested a KC-analogue for the uvwxy-Iemma.  ... 
doi:10.1007/bfb0035780 fatcat:2tbil233dfbzlljqpy72gco7pq

A Survey on the Local Divisor Technique [article]

Volker Diekert, Manfred Kufleitner
2015 arXiv   pre-print
These applications include linear temporal logic, rational expressions with Kleene stars restricted to prefix codes with bounded synchronization delay, Church-Rosser congruential languages, and Simon's  ...  We also introduce the notion of localizable language class as a new abstract concept which unifies some of the proofs for the results above.  ...  Acknowledgements We thank the anonymous reviewers for their numerous suggestions which significantly improved the presentation.  ... 
arXiv:1410.6026v3 fatcat:h53cmqkxebcvhdkpdbyjnm3rva

A New Approach to Formal Language Theory by Kolmogorov Complexity [article]

Ming Li and Paul Vitanyi (CWI and University of Amsterdam)
2001 arXiv   pre-print
The main results presented here are an alternative for pumping lemma(s), a new characterization for regular languages, and a new method to separate deterministic context-free languages and nondeterministic  ...  context-free languages.  ...  We thank Peter van Emde Boas, Theo Jansen, Tao Jiang for reading the manuscript and commenting on it, and the anonymous referees for extensive comments and suggestions for improvements.  ... 
arXiv:cs/0110040v1 fatcat:qpcm5npokjb6pewwvfxguc7go4

Deciding determinism of caterpillar expressions

Kai Salomaa, Sheng Yu, Jinfeng Zan
2009 Theoretical Computer Science  
Caterpillar expressions have been introduced by Brüggemann-Klein and Wood for applications in markup languages.  ...  Here we give a formal definition of determinism of caterpillar expressions that is based on the language of instruction sequences defined by the expression.  ...  In the time bound the function f depends exponentially on k but, since the branching occurs only when the current prefixes coincide, in fact, on most inputs the running time should be essentially better  ... 
doi:10.1016/j.tcs.2009.03.010 fatcat:ogazb5rznfgwhagjg2km63guei

Page 6186 of Mathematical Reviews Vol. , Issue 91K [page]

1991 Mathematical Reviews  
A language A over a finite alphabet is called a p-language [f-language, b-language] if every class of the right (principal) congruence determined by A is a prefix code [finite set, bounded set].  ...  Most of the references are to papers that deal with DOL theory, but the concept of a bounded language, as used in the theory of context-free languages, and the concept of a locally testable language, as  ... 

Primitive words and roots of words [article]

Gerhard Lischke
2011 arXiv   pre-print
We examine the powers of languages for different sets of exponents, and especially their regularity and context-freeness, in Section 5, and the decidability of appropriate questions in Section 6.  ...  In the algebraic theory of codes and formal languages, the set Q of all primitive words over some alphabet has received special interest.  ...  Acknowledgements The author is grateful to Antal Iványi in Budapest for his suggestion to write this paper, for Martin Hünniger in Jena for his help with the figures, and to Peter Leupold in Kassel and  ... 
arXiv:1104.4427v1 fatcat:5h6435drijg7vdy2bzw36leiqu
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