Perpetuality and strong normalization in orthogonal term rewriting systems

  • Zurab Khasidashvili
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 775)


We design a strategy that for any given term t in an Orthogonal Term Rewriting System (OTRS) constructs a longest reduction starting from t if t is strongly normalizable, and constructs an infinite reduction otherwise. For some classes of OTRSs the strategy is easily computable. We develop a method for finding the least upper bound of lengths of reductions starting from a strongly normalizable term. We give also some applications of our results.


Normal Form Combinatory Logic Limit Strategy Strong Normalization Proof Sketch 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Zurab Khasidashvili
    • 1
  1. 1.School of Information SystemsUEANorwichEngland

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