An O(log n) expected rounds randomized byzantine generals protocol
Journal of the ACM (JACM)
Discrete Mathematics - First Japan Conference on Graph Theory and Applications
ACM Computing Surveys (CSUR)
A threshold of ln n for approximating set cover (preliminary version)
STOC '96 Proceedings of the twenty-eighth annual ACM symposium on Theory of computing
On the hardness of approximating minimization problems
Journal of the ACM (JACM)
The Byzantine Generals Problem
ACM Transactions on Programming Languages and Systems (TOPLAS)
Non-approximability results for optimization problems on bounded degree instances
STOC '01 Proceedings of the thirty-third annual ACM symposium on Theory of computing
Approximation algorithms
Hardness of Approximating Problems on Cubic Graphs
CIAC '97 Proceedings of the Third Italian Conference on Algorithms and Complexity
FCT'11 Proceedings of the 18th international conference on Fundamentals of computation theory
Complexity of majority monopoly and signed domination problems
Journal of Discrete Algorithms
On the approximability and exact algorithms for vector domination and related problems in graphs
Discrete Applied Mathematics
Alliance free sets in Cartesian product graphs
Discrete Applied Mathematics
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We consider inapproximability for two graph optimisation problems called monopoly and partial monopoly. We prove that these problems cannot be approximated within a factor of (1/3 - 驴) ln n and (1/2 - 驴) lnn, unless NP 驴 Dtime(nO(log log n)), respectively. We also show that, if 驴 is the maximum degree in a graph G, then both problems cannot be approximated within a factor of ln 驴-O(ln ln 驴), unless P = NP, though both these problems can be approximated within a factor of ln(驴) + O(1). Finally, for cubic graphs, we give a 1.6154 approximation algorithm for the monopoly problem and a 5/3 approximation algorithm for partial monopoly problem, and show that they are APX-complete.