Easily Refutable Subformulas of Large Random 3CNF Formulas
نویسندگان
چکیده
A simple nonconstructive argument shows that most CNF formulas with clauses (where is a large enough constant) are not satisfiable. It is an open question whether there is an efficient refutation algorithm that for most formulas with clauses proves that they are not satisfiable. We present a polynomial time algorithm that for most CNF formulas with clauses (where is a large enough constant) finds a subformula with clauses and then proves that this subformula is not satisfiable (and hence that the original formula is not satisfiable). Previously, it was only known how to efficiently certify the unsatisfiability of random CNF formulas with at least poly clauses.
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