Max k-cut and approximating the chromatic number of random graphs

  • Authors:
  • Amin Coja-Oghlan;Cristopher Moore;Vishal Sanwalani

  • Affiliations:
  • Humboldt-Universität zu Berlin, Institut für Informatik, Berlin, Germany;Universityof New Mexico, Albuquerque, NM;Universityof New Mexico, Albuquerque, NM

  • Venue:
  • ICALP'03 Proceedings of the 30th international conference on Automata, languages and programming
  • Year:
  • 2003

Quantified Score

Hi-index 0.00

Visualization

Abstract

We consider the MAX k-CUT problem in random graphs Gn,p. First, we estimate the probable weight of a MAX k-CUT using probabilistic counting arguments and byanaly zing a simple greedy heuristic. Then, we give an algorithm that approximates MAX k-CUT within expected polynomial time. The approximation ratio tends to 1 as np → ∞. As an application, we obtain an algorithm for approximating the chromatic number of Gn,p, 1/n ≤ p ≤ 1/2, within a factor of O(√np) in polynomial expected time, thereby answering a question of Krivelevich and Vu, and extending a result of Coja-Oghlan and Taraz. We give similar algorithms for random regular graphs Gn,r.