Approximation Algorithms for Intersection Graphs

@article{Kammer2012ApproximationAF,
  title={Approximation Algorithms for Intersection Graphs},
  author={Frank Kammer and Torsten Tholey and Heiko Voepel},
  journal={Algorithmica},
  year={2012},
  volume={68},
  pages={312-336}
}
We study three complexity parameters that, for each vertex v, are an upper bound for the number of cliques that are sufficient to cover a subset S(v) of its neighbors. We call a graph k-perfectly groupable if S(v) consists of all neighbors, k-simplicial if S(v) consists of the neighbors with a higher number after assigning distinct numbers to all vertices, and k-perfectly orientable if S(v) consists of the endpoints of all outgoing edges from v for an orientation of all edges. These parameters… 

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