On the number of contractible triples in 3-connected graphs
نویسنده
چکیده
McCuaig and Ota proved that every 3-connected graph G on at least 9 vertices admits a contractible triple, i. e. a connected subgraph H on three vertices such that G − V (H) is 2-connected. Here we show that every 3-connected graph G on at least 9 vertices has more than |V (G)|/10 many contractible triples. If, moreover, G is cubic, then there are at least |V (G)|/3 many contractible triples, which is best possible. AMS classification: 05c40, 05c75.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 98 شماره
صفحات -
تاریخ انتشار 2008