On languages satisfying “interchange Lemma”
نویسندگان
چکیده
منابع مشابه
Ogden's Lemma for Regular Tree Languages
Pumping lemmata are elementary tools for the analysis of formal languages. While they usually cannot be made strong enough to fully capture a class of languages, it is generally desirable to have as strong pumping lemmata as possible. However, this is counterbalanced by the experience that strong pumping lemmata may be hard to prove, or, worse, hard to use—this experience has been made, for exa...
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There are various pumping lemmata for context free languages, the strongest of which is Ogden’s Lemma. It is known that it does not fully characterize context free languages. In an attempt to remedy the situation, Manaster– Ramer, Moshier and Zeitman have strengthened this lemma. As we shall show here, there exist non–semilinear languages that satisfy this stronger lemma and also the lesser kno...
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We study a pumping lemma for the word/tree languages generated by higher-order grammars. Pumping lemmas are known up to order-2 word languages (i.e., for regular/context-free/indexed languages), and have been used to show that a given language does not belong to the classes of regular/context-free/indexed languages. We prove a pumping lemma for word/tree languages of arbitrary orders, modulo a ...
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This article presents a lemma in the spirit of the pumping lemma for indexed languages but easier to employ. Section
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The concept of macro tree transducer is a formal model for studying properties of syntax{ directed translations and of functional languages which are based on primitive recursion. In this paper, for output languages of producing and nondeleting macro tree transducers, we introduce and prove a pumping lemma. We apply this pumping lemma to gain two results: (1) there is no producing and nondeleti...
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ژورنال
عنوان ژورنال: RAIRO - Theoretical Informatics and Applications
سال: 1993
ISSN: 0988-3754,1290-385X
DOI: 10.1051/ita/1993270100711