Characterization of context-pree languages by erasing automata
It is shown that context-free languages are recognizable by (non-deterministic) erasing automata; thereby a hypothesis of  is denied. In addition, the class of context-free languages is characterized by means of the automata which erase each cell at the second visit at latest.
KeywordsRegular Language Input Word Grammar Rule Terminal Symbol Nondeterministic Automaton
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