Abstract
The syntactic complexity of context-free grammars defined over word monoids is investigated. It is demonstrated that every recursively enumerable language can be defined by a ten-nonterminal context-free grammar over a word monoid generated by an alphabet and six words of length two. Open problems are formulated.
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Meduna, A. Syntactic complexity of context-free grammars over word monoids. Acta Informatica 33, 457–462 (1996). https://doi.org/10.1007/s002360050052
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DOI: https://doi.org/10.1007/s002360050052