Even Shorter Proofs Without New Variables

Author Adrián Rebola-Pardo



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Adrián Rebola-Pardo
  • Technische Universität Wien, Austria
  • Johannes Kepler Universität Linz, Austria

Acknowledgements

I would like to thank Georg Weissenbacher for the discussions on WSR, as well as the anonymous reviewers who provided very useful comments.

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Adrián Rebola-Pardo. Even Shorter Proofs Without New Variables. In 26th International Conference on Theory and Applications of Satisfiability Testing (SAT 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 271, pp. 22:1-22:20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)
https://doi.org/10.4230/LIPIcs.SAT.2023.22

Abstract

Proof formats for SAT solvers have diversified over the last decade, enabling new features such as extended resolution-like capabilities, very general extension-free rules, inclusion of proof hints, and pseudo-boolean reasoning. Interference-based methods have been proven effective, and some theoretical work has been undertaken to better explain their limits and semantics. In this work, we combine the subsumption redundancy notion from [Sam Buss and Neil Thapen, 2019] and the overwrite logic framework from [Adrián Rebola{-}Pardo and Martin Suda, 2018]. Natural generalizations then become apparent, enabling even shorter proofs of the pigeonhole principle (compared to those from [Marijn J. H. Heule et al., 2017]) and smaller unsatisfiable core generation.

Subject Classification

ACM Subject Classification
  • Hardware → Theorem proving and SAT solving
Keywords
  • Interference
  • SAT solving
  • Unsatisfiability proofs
  • Unsatisfiable cores

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