Constructions of k-critical P5-free graphs
نویسندگان
چکیده
4 With respect to a class C of graphs, a graph G ∈ C is said to be k-critical if every proper 5 subgraph of G belonging to C is k−1 colorable. We construct an infinite set of k-critical P56 free graphs for every k ≥ 5. We also prove that there are exactly eight 5-critical {P5, C5}-free 7 graphs. 8
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 182 شماره
صفحات -
تاریخ انتشار 2015