A pumping lemma for random permitting context languages

Authors:
Sigrid Ewert;Andries van der Walt
Affiliations:
Univ. of the Witwatersrand, Johannesburg, South Africa;Univ. of Stellenbosch, Matieland, South Africa
Venue:
Theoretical Computer Science
Year:
2002

Citing 3
Cited 10

A shrinking lemma for random forbidding context languages

Theoretical Computer Science
Introduction To Automata Theory, Languages, And Computation

Introduction To Automata Theory, Languages, And Computation
Regulated Rewriting in Formal Language Theory

Regulated Rewriting in Formal Language Theory

A property of random context picture grammars

Theoretical Computer Science
A Note on the Generative Power of Some Simple Variants of Context-Free Grammars Regulated by Context Conditions

LATA '09 Proceedings of the 3rd International Conference on Language and Automata Theory and Applications
Left-forbidding cooperating distributed grammar systems

Theoretical Computer Science
Simple restriction in context-free rewriting

Journal of Computer and System Sciences
On erasing productions in random context grammars

ICALP'10 Proceedings of the 37th international colloquium conference on Automata, languages and programming: Part II
On the complexity of szilard languages of regulated grammars

ICTAC'11 Proceedings of the 8th international conference on Theoretical aspects of computing
On restricted context-free grammars

Journal of Computer and System Sciences
Ogden's lemma for ET0L languages

LATA'12 Proceedings of the 6th international conference on Language and Automata Theory and Applications
Necessary conditions for subclasses of random context languages

Theoretical Computer Science
On the power of permitting features in cooperating context-free array grammar systems

Discrete Applied Mathematics

Quantified Score

Hi-index	5.23

Visualization

Abstract

Random context grammars belong to the class of context-free grammars with regulated rewriting. Their productions depend on context that may be randomly distributed in a sentential form. Context is classified as either permitting or forbidding, where permitting context enables the application of a production and forbidding context inhibits it. For random context languages of finite index a generalization of the well-known pumping lemma for context-free languages has been proven. We drop the finite index restriction and concentrate on non-erasing grammars that use permitting context only. We prove a pumping lemma for their languages that generalizes and refines the existing one, and show that these grammars are strictly weaker than the non-erasing random context grammars