Hard examples for resolution

Alasdair Urquhart

Journal of the ACM · 1987 · 446 citations · 10 references

DOIFull text

Open access

Concepts

Abstract

Exponential lower bounds are proved for the length-of-resolution refutations of sets of disjunctions constructed from expander graphs, using the method of Tseitin. Since these sets of clauses encode biconditionals, they have short (polynomial-length) refutations in a standard axiomatic formulation of propositional calculus.

References

10