Counting models for 2SAT and 3SAT formulae

@article{Dahllf2005CountingMF,
  title={Counting models for 2SAT and 3SAT formulae},
  author={Vilhelm Dahll{\"o}f and P. Jonsson and Magnus Wahlstr{\"o}m},
  journal={Theor. Comput. Sci.},
  year={2005},
  volume={332},
  pages={265-291}
}
We here present algorithms for counting models and max-weight models for 2SAT and 3SAT formulae. They use polynomial space and run in O(1.2561n) and O(1.6737n) time, respectively, where n is the number of variables. This is faster than the previously best algorithms for counting nonweighted models for 2SAT and 3SAT, which run in O(1.3247n) and O(1.6894n) time, respectively. In order to prove these time bounds, we develop new measures of formula complexity, allowing us to conveniently analyze… Expand
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