Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with A. Steger, D. Steurer and B. Sudakov)

Mittagsseminar Talk Information

Date and Time: Thursday, March 13, 2008, 12:15 pm

Duration: This information is not available in the database

Location: OAT S15/S16/S17

Speaker: Dominik Scheder

How many conflicts does it need to be unsatisfiable?

A pair of clauses in a CNF formula constitutes a conflict if they contain complementary literals. For example, (x OR y) and (~x OR z) constitute a conflict, but (x OR y) and (x OR u) do not.

Clearly, an unsatisfiable CNF formula must have (many) conflicts. We try to determine this number for k-CNF formulas (i.e., where every clause has exactly k literals) as a function of k. So we ask the following question: What is the minimum number of conflicts in an unsatisfiable k-CNF formula?

A lower bound of 2^k and an upper bound of {2^k \choose 2} are pretty straight-forward. We will show that the number of conflicts is at least 2.3^k.

Joint work with Philipp Zumstein.

Back to Upcoming talks

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2024  2023  2022  2021  2020  2019  2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks

Automatic MiSe System Software Version 1.4803M   |   admin login