Tree coloring of distance graphs with a real interval set

نویسندگان

  • Lian-Cui Zuo
  • Qinglin Yu
  • Jian-Liang Wu
چکیده

Let R be the set of real numbers and D be a subset of the positive real numbers. The distance graph G(R, D) is a graph with the vertex set R and two vertices x and y are adjacent if and only if |x − y| ∈ D. In this work, the vertex arboricity (i.e., the minimum number of subsets into which the vertex set V (G) can be partitioned so that each subset induces an acyclic subgraph) of G(R, D) is determined for D being an interval between 1 and δ. c © 2006 Elsevier Ltd. All rights reserved.

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عنوان ژورنال:
  • Appl. Math. Lett.

دوره 19  شماره 

صفحات  -

تاریخ انتشار 2006