Equations in free partially commutative monoids

  • Christine Duboc
Contributed Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 210)


We characterize the solutions of all the equations in two unknowns in the free partially commutative monolds. We show that the solutions are basically cyclic. Afterwards, we define the transposition (t and t′ are transposed iff t=xy and t′=yx) and the conjugacy relations (t and t′ are conjugate iff tλ=λt′). We show that the conjugacy is the transitive closure of the transposition and that the set of conjugacy factors λ is a recognizable subset of the partially commutative monoid.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • Christine Duboc
    • 1
  1. 1.Laboratoire d'informatiqueUniversité de RouenMont Saint AignanFrance

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