• Corpus ID: 5656269

Approximations for λ-Colorings of Graphs 201

  title={Approximations for $\lambda$-Colorings of Graphs 201},
  author={Hans L. Bodlaender and Ton Kloks and Richard B. Tan and Jan van Leeuwen},
A λ-coloring of a graph G is an assignment of colors from the integer set {0, . . . , λ} to the vertices of the graph G such that vertices at distance of at most two get different colors and adjacent vertices get colors which are at least two apart. The problem of finding λ-colorings with optimal or near-optimal λ arises in the context of radio frequency assignment. We show that the problem of finding the minimum λ for planar graphs, bipartite graphs, chordal graphs and split graphs is NP… 

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