Proper down-coloring acyclic digraphs
نویسندگان
چکیده
We consider vertex coloring of an acyclic digraph ~ G in such a way that two vertices which have a common ancestor in ~ G receive distinct colors. Such colorings arise in a natural way when clustering, indexing and bounding space for various genetic data for efficient analysis. We discuss the corresponding chromatic number and derive an upper bound as a function of the maximum number of descendants of a given vertex and the inductiveness of the corresponding hypergraph, which is obtained from the original digraph. 2000 MSC: 05C15, 05C20, 05C65, 05C85, 05D90, 06A05.
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