Crossing by lines all edges of a line arrangement
نویسنده
چکیده
Let L be a family of n blue lines in the real projective plane. Suppose that R is a collection of m red lines, different from the blue lines, and it is known that every edge in the arrangement A(L) is crosses by a line in R. We show that m ≥ n−1 3.5 . Our result is more general and applies to pseudo-line arrangements A(L), and even weaker assumptions are required for R.
منابع مشابه
Crossing edges and faces of line arrangements in the plane
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 313 شماره
صفحات -
تاریخ انتشار 2013