An Improved Separation of Regular Resolution from Pool Resolution and Clause Learning

  • Maria Luisa Bonet
  • Sam Buss
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7317)


We prove that the graph tautology principles of Alekhnovich, Johannsen, Pitassi and Urquhart have polynomial size pool resolution refutations that use only input lemmas as learned clauses and without degenerate resolution inferences. These graph tautology principles can be refuted by polynomial size DPLL proofs with clause learning, even when restricted to greedy, unit-propagating DPLL search.


Partial Order Resolution Variable Polynomial Size General Resolution Empty Clause 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Maria Luisa Bonet
    • 1
  • Sam Buss
    • 2
  1. 1.Lenguajes y Sistemas InformáticosUniversidad Politécnica de CataluñaBarcelonaSpain
  2. 2.Department of MathematicsUniversity of CaliforniaSan DiegoUSA

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