Separating Cycles in Doubly Toroidal Embeddings
نویسندگان
چکیده
We show that every 4-representative graph embedding in the double torus contains a noncontractible cycle which separates the surface into two pieces. This improves a result of Zha and Zhao for general orientable surfaces, in which the same conclusion holds for 6-representative graph embeddings. Noncontractible separating cycles have been studied because they provide a way to do induction on the genus of a graph embedding.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 19 شماره
صفحات -
تاریخ انتشار 2003