The number of contractible edges in a 4-connected graph having a contractible edge not contained in triangles
نویسنده
چکیده
Let G be a 4-connected graph, let Ẽ(G) denote the set of those edges of G which are not contained in a triangle, and let Ec(G) denote the set of 4-contractible edges of G. We show that if |Ẽ(G)| ≥ 1, then |Ec(G)| ≥ (|Ẽ(G)|+ 8)/4 unless G satisfies certain conditions.
منابع مشابه
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عنوان ژورنال:
- Australasian J. Combinatorics
دوره 68 شماره
صفحات -
تاریخ انتشار 2017