On the vertex-arboricity of planar graphs
نویسندگان
چکیده
The vertex-arboricity a(G) of a graph G is the minimum number of subsets into which the set of vertices of G can be partitioned so that each subset induces a forest. It is well-known that a(G) ≤ 3 for any planar graph G. In this paper we prove that a(G) ≤ 2 whenever G is planar and either G has no 4-cycles or any two triangles of G are at distance at least 3. c © 2007 Elsevier Ltd. All rights reserved.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 29 شماره
صفحات -
تاریخ انتشار 2008