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Solvability of Context Equations with Two Context Variables Is Decidable

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Automated Deduction — CADE-16 (CADE 1999)

Part of the book series: Lecture Notes in Computer Science ((LNAI,volume 1632))

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Abstract

Context unification is a natural variant of second order unification that represents a generalization of word unification at the same time. While second order unification is wellknown to be undecidable and word unification is decidable it is currently open if solvability of context equations is decidable. We show that solvability of systems of context equations with two context variables is decidable. The context variables may have an arbitrary number of occurrences, and the equations may contain an arbitrary number of individual variables as well. The result holds under the assumption that the first-order background signature is finite

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Author information

Authors and Affiliations

  1. Fachbereich Informatik, J.-W.-Goethe-Universität, Postfach 11 19 32, D-60054, Frankfurt, Germany

    Manfred Schmidt-Schauß

  2. CIS, University of Munich, Oettingenstr 67, D-80538, München, Germany

    Klaus U. Schulz

Authors
  1. Manfred Schmidt-Schauß
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  2. Klaus U. Schulz
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© 1999 Springer-Verlag Berlin Heidelberg

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Schmidt-Schauß, M., Schulz, K.U. (1999). Solvability of Context Equations with Two Context Variables Is Decidable. In: Automated Deduction — CADE-16. CADE 1999. Lecture Notes in Computer Science(), vol 1632. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-48660-7_5

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  • DOI: https://doi.org/10.1007/3-540-48660-7_5

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-66222-8

  • Online ISBN: 978-3-540-48660-2

  • eBook Packages: Springer Book Archive

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