Phase transitions in the regular random 3-SAT problem

  • Ramón Béjar
  • Felip Manyà
Communications 3B Logics for AI
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1609)


In this paper we investigate phase transitions in the random 3-SAT problem but we move from the usual setting of classical logic to the more general setting of multiple-valued logics. We deal with regular CNF formulas and use a generalized Davis-Putnam (DP) procedure for testing their satisfiability. We establish the location of the threshold for different cardinalities of the truth value set and show experimentally that the location of the threshold increases logarithmically in the cardinality of the truth value set. We also provide a theoretical explanation of this fact. The DP procedure and the classical random 3-SAT problem appear to be a particular case of our approach.


Multiple-valued logics regular CNF formulas satisfiability phase transitions threshold benchmarks 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Ramón Béjar
    • 1
  • Felip Manyà
    • 1
  1. 1.Department d’InformàticaUniversitat de LleidaLleidaSpain

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