Covering planar graphs with forests
نویسندگان
چکیده
We study the problem of covering graphs with trees and a graph of bounded maximum degree. By a classical theorem of Nash-Williams, every planar graph can be covered by three trees. We show that every planar graph can be covered by two trees and a forest, and the maximum degree of the forest is at most 8. Stronger results are obtained for some special classes of planar graphs.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 94 شماره
صفحات -
تاریخ انتشار 2005