Discrete & Computational Geometry

, Volume 20, Issue 2, pp 155–161 | Cite as

Straight line arrangements in the real projective plane

  • D. Forge
  • J. L. Ramírez Alfonsín


Let A be an arrangement of n pseudolines in the real projective plane and let p 3(A) be the number of triangles of A. Grünbaum has proposed the following question. Are there infinitely many simple arrangements of straight lines with p 3(A)=1/3n(n−1)? In this paper we answer this question affirmatively.


Discrete Comput Geom Marie Curie Infinite Family Recursive Method Line Arrangement 
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Copyright information

© Springer-Verlag 1998

Authors and Affiliations

  • D. Forge
    • 1
  • J. L. Ramírez Alfonsín
    • 2
  1. 1.Université Pierre et Marie Curie, Paris 6, case 189Paris Cedex 05France
  2. 2.Instituto de MatemáticasUniversidad Nacional Autónoma de México, Area de la Investigacion Cientifica, Circuito Exterior, C.U.Mexico

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