K6-minors in triangulations and complete quadrangulations
نویسندگان
چکیده
In this paper, we shall prove that a projective-planar (resp., toroidal) triangulation G has K6 as a minor if and only if G has no quadrangulation isomorphic to K4 (resp., K5) as a subgraph. As a application of the theorems, we can prove that Hadwiger’s conjecture is true for projective-planar and toroidal triangulations.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 60 شماره
صفحات -
تاریخ انتشار 2009