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Vertex decompositions of sparse graphs into an edgeless subgraph and a subgraph of maximum degree at most k

✍ Scribed by O. V. Borodin; A. O. Ivanova; M. Montassier; P. Ochem; A. Raspaud


Publisher
John Wiley and Sons
Year
2009
Tongue
English
Weight
127 KB
Volume
65
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

A graph G is (k,0)‐colorable if its vertices can be partitioned into subsets V~1~ and V~2~ such that in G[V~1~] every vertex has degree at most k, while G[V~2~] is edgeless. For every integer k⩾0, we prove that every graph with the maximum average degree smaller than (3__k__+4)/(k+2) is (k,0)‐colorable. In particular, it follows that every planar graph with girth at least 7 is (8, 0)‐colorable. On the other hand, we construct planar graphs with girth 6 that are not (k,0)‐colorable for arbitrarily large k. © 2009 Wiley Periodicals, Inc. J Graph Theory 65:83–93, 2010