Abstract
A resolution proof of an unsatisfiable propositional formula in conjunctive normal form is a “Davis-Putnam resolution proof” iff there exists a sequence of the variables of the formula such thatx is eliminated (with the resolution rule) beforey on any branch of the proof tree representing the resolution proof, only ifx is beforey in this sequence. Davis-Putnam resolution is one of several resolution restrictions. It is complete. We present an infinite family of unsatisfiable propositional formulas and show: These formulas have unrestricted resolution proofs whose length is polynomial in their size. All Davis-Putnam resolution proofs of these formulas are of superpolynomial length. In the terminology of [4, definition 1.5]: Davis-Putnam resolution does notp-simulate unrestricted resolution.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
