Total Space in Resolution Is at Least Width Squared
نویسنده
چکیده
Given an unsatisfiable k-CNF formula φ we consider two complexity measures in Resolution: width and total space. The width is the minimal W such that there exists a Resolution refutation of φ with clauses of at most W literals. The total space is the minimal size T of a memory used to write down a Resolution refutation of φ, where the size of the memory is measured as the total number of literals it can contain. We prove that T = Ω((W − k)).
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