An undecidable property of context-free languages
Formal Languages and Automata Theory
2010-04-13 v1 Discrete Mathematics
Abstract
We prove that there exists no algorithm to decide whether the language generated by a context-free grammar is dense with respect to the lexicographic ordering. As a corollary to this result, we show that it is undecidable whether the lexicographic orderings of the languages generated by two context-free grammars have the same order type.
Cite
@article{arxiv.1004.1736,
title = {An undecidable property of context-free languages},
author = {Zoltan Esik},
journal= {arXiv preprint arXiv:1004.1736},
year = {2010}
}