The Confluence Problem for Flat TRSs

  • Ichiro Mitsuhashi
  • Michio Oyamaguch
  • Florent Jacquemard
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4120)


We prove that the properties of reachability, joinability and confluence are undecidable for flat TRSs. Here, a TRS is flat if the heights of the left and right-hand sides of each rewrite rule are at most one.


Term rewriting system Decision problem Confluence Flat 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Ichiro Mitsuhashi
    • 1
  • Michio Oyamaguch
    • 1
  • Florent Jacquemard
    • 2
  1. 1.Mie University 
  2. 2.INRIA-Futurs and LSV, UMR CNRS ENS Cachan 

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