# Approximations for λ-Colorings of Graphs 201

@inproceedings{Bodlaender2004ApproximationsF, title={Approximations for $\lambda$-Colorings of Graphs 201}, author={Hans L. Bodlaender and Ton Kloks and Richard B. Tan and Jan van Leeuwen}, year={2004} }

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…

## 7 Citations

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An \(L(2,1)\)-labeling problem is a particular case of \(L(h,k)\)-labeling problem. An \(L(2,1)\)-labeling of a graph \(G=(V,E)\) is a function \(f\) from the set of vertices \(V\) to the set of…

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