Planarity of iterated line graphs
نویسندگان
چکیده
The line index of a graph G is the smallest k such that the kth iterated line graph of G is nonplanar. We show that the line index of a graph is either infinite or it is at most 4. Moreover, we give a full characterization of all graphs with respect to their line index. © 2007 Elsevier B.V. All rights reserved.
منابع مشابه
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عنوان ژورنال:
- Discrete Mathematics
دوره 308 شماره
صفحات -
تاریخ انتشار 2008