Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
421423 | Discrete Applied Mathematics | 2007 | 9 Pages |
Abstract
The (2,1)(2,1)-total labelling number λ2T(G) of a graph G is the width of the smallest range of integers that suffices to label the vertices and the edges of G such that no two adjacent vertices have the same label, no two adjacent edges have the same label and the difference between the labels of a vertex and its incident edges is at least 2. In this paper we prove that if G is an outerplanar graph with maximum degree Δ(G)Δ(G), then λ2T(G)⩽Δ(G)+2 if Δ(G)⩾5Δ(G)⩾5, or Δ(G)=3Δ(G)=3 and G is 2-connected, or Δ(G)=4Δ(G)=4 and G contains no intersecting triangles.
Keywords
Related Topics
Physical Sciences and Engineering
Computer Science
Computational Theory and Mathematics
Authors
Dong Chen, Weifan Wang,