Relative length of longest paths and longest cycles in triangle-free graphs
نویسندگان
چکیده
In this paper, we study triangle-free graphs. Let G = (VG, EG) be an arbitrary triangle-free graph with minimum degree at least two and σ4(G) ≥ |VG|+2. We first show that either for any path P in G there exists a cycle C such that |VP \ VC | ≤ 1, or G is isomorphic to exactly one exception. Using this result, we show that for any set S of at most δ vertices in G there exists a cycle C such that S ⊆ VC .
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 308 شماره
صفحات -
تاریخ انتشار 2008