Some Undecidable Problems Related to the Herbrand Theorem
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چکیده
March 1997 (revised July 1997) ISSN 1100{0686 Some Undecidable Problems Related to the Herbrand Theorem Yuri Gurevich Margus Veanes EECS Department Computing Science Department University of Michigan Uppsala University Ann Arbor, MI 48109-2122 Box 311, S-751 05 Uppsala USA Sweden [email protected] [email protected] Abstract We improve upon a number of recent undecidability results related to the so-called Herbrand Skeleton Problem, the Simultaneous Rigid E-Uni cation Problem and the prenex fragment of intuitionistic logic with equality.
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