The average degree of an edge-chromatic critical graph
نویسنده
چکیده
A graph G with maximum degree and edge chromatic number ′(G)> is edge-critical if ′(G− e)= for every edge e of G. New lower bounds are given for the average degree of an edge-critical graph, which improve on the best bounds previously known for most values of . Examples of edge-critical graphs are also given. In almost all cases, there remains a large gap between the best lower bound known and the smallest average degree of any known edge-critical graph. © 2007 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 56 شماره
صفحات -
تاریخ انتشار 2007