On Translating Lambek Grammars with One Division into Context-Free Grammars
نویسنده
چکیده
In this paper we describe a method of translating a Lambek grammar with one division into an equivalent context-free grammar whose size is bounded by a polynom from the size of the original grammar. Earlier constructions by Buszkowski and Pentus lead to exponential growth of the grammar size. 1 Lambek Grammars and Context-Free Gram-
منابع مشابه
Lambek Calculus and Formal Grammars
The question about the position of categorial grammars in the Chomsky hierarchy arose in late 1950s and early 1960s. In 1960 Bar-Hillel, Gaifman, and Shamir [1] proved that a formal language can be generated by some basic categorial grammar if and only if the language is context-free. They conjectured (see also [7]) that the same holds for Lambek grammars, i. e., for categorial grammars based o...
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