Extended Resolution Simulates DRAT

  • Benjamin Kiesl
  • Adrián Rebola-Pardo
  • Marijn J. H. Heule
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10900)


We prove that extended resolution—a well-known proof system introduced by Tseitin—polynomially simulates \({\mathsf {DRAT}}\), the standard proof system in modern SAT solving. Our simulation procedure takes as input a \({\mathsf {DRAT}}\) proof and transforms it into an extended-resolution proof whose size is only polynomial with respect to the original proof. Based on our simulation, we implemented a tool that transforms \({\mathsf {DRAT}}\) proofs into extended-resolution proofs. We ran our tool on several benchmark formulas to estimate the increase in size caused by our simulation in practice. Finally, as a side note, we show how blocked-clause addition—a generalization of the extension rule from extended resolution—can be used to replace the addition of resolution asymmetric tautologies in \({\mathsf {DRAT}}\) without introducing new variables.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Benjamin Kiesl
    • 1
  • Adrián Rebola-Pardo
    • 1
  • Marijn J. H. Heule
    • 2
  1. 1.Institute of Logic and ComputationTU WienViennaAustria
  2. 2.Department of Computer ScienceThe University of TexasAustinUSA

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