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Unification in combinations of collapse-free theories with disjoint sets of function symbols

  • Unification Theory
  • Conference paper
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Book cover 8th International Conference on Automated Deduction (CADE 1986)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 230))

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Abstract

A unification algorithm for combinations of collapse-free equational theories with disjoint sets of function symbols is presented. The algorithm uses complete unification algorithms for the theories in the combination to compute complete sets of unifiers in the combined theory. It terminates if the algorithms for the theories in the combination terminate. The only restriction on the theories in the combination — apart from disjointness of function symbol sets — is that they must be collapse-free (i.e., they must not have axioms of the form t=x, where t is a non-variable term and x is a variable). This extends the class of equational theories for which the unification problem in combinations can be solved to collapse-free theories. The algorithm is based on a study of the properties of unifiers in combination of non-regular collapse-free theories.

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Author notes

  1. Erik Tidén

    Present address: Swedish Institute of Computer Science (SICS), Box 1193, S-163 62, Spånga, Sweden

Authors and Affiliations

  1. Department of Computing Science, Royal Institute of Technology, Stockholm

    Erik Tidén

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  1. Erik Tidén
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Jörg H. Siekmann

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© 1986 Springer-Verlag Berlin Heidelberg

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Tidén, E. (1986). Unification in combinations of collapse-free theories with disjoint sets of function symbols. In: Siekmann, J.H. (eds) 8th International Conference on Automated Deduction. CADE 1986. Lecture Notes in Computer Science, vol 230. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-16780-3_110

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  • DOI: https://doi.org/10.1007/3-540-16780-3_110

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-16780-8

  • Online ISBN: 978-3-540-39861-5

  • eBook Packages: Springer Book Archive

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