论文信息 - Well quasi-orders and context-free grammars

Well quasi-orders and context-free grammars

Let G be a context-free grammar and let L be the language of all the words derived from any variable of G. We prove the following generalization of Higman's theorem: any division order on L is a well quasi-order on L. We also give applications of this result to some quasi-orders associated with unitary grammars.

Flavio D'Alessandro | Stefano Varricchio | Flavio D'Alessandro | S. Varricchio

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