The Copying Power of Well-Nested Multiple Context-Free Grammars
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چکیده
We prove a copying theorem for well-nested multiple contextfree languages: if L = {w#w | w ∈ L0 } has a well-nested m-MCFG, then L has a ‘non-branching’ well-nested m-MCFG. This can be used to give simple examples of multiple context-free languages that are not generated by any well-nested MCFGs.
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تاریخ انتشار 2010