Triangles in arrangements of lines. II
Author: George Purdy
Journal: Proc. Amer. Math. Soc. 79 (1980), 77-81
MSC: Primary 05B35; Secondary 52A40
MathSciNet review: 560588
Abstract: We show that given n lines in the real projective plane, no of which are concurrent, the number of triangular regions formed is at most , equality being possible.
We also show that if then . Grünbaum has conjectured .
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