Resolution Trees with Lemmas: Resolution Refinements that Characterize DLL Algorithms with Clause Learning

@article{Buss2008ResolutionTW,
  title={Resolution Trees with Lemmas: Resolution Refinements that Characterize DLL Algorithms with Clause Learning},
  author={Samuel R. Buss and Jan Hoffmann and Jan Johannsen},
  journal={ArXiv},
  year={2008},
  volume={abs/0811.1075}
}
Resolution refinements called w-resolution trees with lemmas (WRTL) and with input lemmas (WRTI) are introduced. Dag-like resolution is equivalent to both WRTL and WRTI when there is no regularity condition. For regular proofs, an exponential separation between regular dag-like resolution and both regular WRTL and regular WRTI is given. It is proved that DLL proof search algorithms that use clause learning based on unit propagation can be polynomially simulated by regular WRTI. More generally… Expand
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