Toughness threshold for the existence of 2-walks in K4-minor-free graphs
نویسندگان
چکیده
We show that every K4-minor free graph with toughness greater than 4/7 has a 2-walk, i.e., a closed walk visiting each vertex at most twice. We also give an example of a 4/7-tough K4-minor free graph with no 2-walk.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 310 شماره
صفحات -
تاریخ انتشار 2010