On removable edges in 3-connected cubic graphs
نویسندگان
چکیده
A removable edge in a 3−connected cubic graph G is an edge e = uv such that the cubic graph obtained from G \ {u, v} by adding an edge between the two neighbours of u distinct from v and an edge between the two neighbours of v disctinct from u is still 3−connected. Li and Wu [3] showed that a spanning tree in a 3−connected cubic graph avoids at least two removable edges, and Kang, Li and Wu [4] showed that a spanning tree contains at least two removable edges. We show here how to obtain these results easily from the structure of the sets of non removable edges and we give a characterization of the extremal graphs for these two results.
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عنوان ژورنال:
- Graphs and Combinatorics
دوره 7 شماره
صفحات -
تاریخ انتشار 1991