Tree-Like Resolution Is Superpolynomially Slower Than DAG-Like Resolution for the Pigeonhole Principle
نویسندگان
چکیده
Our main result shows that a shortest proof size of tree-like resolution for the pigeonhole principle is superpolynomially larger than that of DAG-like resolution. In the proof of a lower bound, we exploit a relationship between tree-like resolution and backtracking, which has long been recognized in this eld but not been used before to give explicit results.
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