On the Number of Upward Planar Orientations of Maximal Planar Graphs
نویسندگان
چکیده
We consider the problem of determining the maximum and the minimum number of upward planar orientations a maximal planar graph can have. We show that n-vertex maximal planar graphs have at least Ω(n · 1.189) and at most O(n · 4) upward planar orientations. Moreover, there exist n-vertex maximal planar graphs having as few as O(n · 2) upward planar orientations and n-vertex maximal planar graphs having Ω(2.599) upward planar orientations.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 544 شماره
صفحات -
تاریخ انتشار 2012