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arXiv · 0710.4499

Remarks on Jurdzinski and Lorys' proof that palindromes are not a Church-Rosser language

Colm O. Dunlaing·Natalie Schluter
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Abstract

In 2002 Jurdzinski and Lorys settled a long-standing conjecture that palindromes are not a Church-Rosser language. Their proof required a sophisticated theory about computation graphs of 2-stack automata. We present their proof in terms of 1-tape Turing machines.We also provide an alternative proof of Buntrock and Otto's result that the set of non-square bitstrings, which is context-free, is not Church-Rosser.

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Colm O. Dunlaing, Natalie Schluter. 2007-10-25. Remarks on Jurdzinski and Lorys' proof that palindromes are not a Church-Rosser language. https://arxiv.org/abs/0710.4499

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