Minimal unsatisfiability: results and open questions
- H. Kleine Büning, X. S. Zhao
- Conference SAT2002,
Restricted on the proof of unsatisfiability of unsatisfiable formulas, a modified DPLL — RSMLS algorithm is presented. The new algorithm has a symmetry rule (Literal renaming ) and three simplified rule ((1,*)-Resolution, Subformula, and Multiple ). As an example, RSMLS algorithm is applied for the proof of unsatisfiability of pigeon-hole formula . We show with respect to RSMLS algorithm that has a refutation tree with at most O(n n n P 1 − n n P 1 − ) nodes.