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Toward the Rectilinear Crossing Number of $K_n$: New Drawings, Upper Bounds, and Asymptotics

Alex Brodsky·Stephane Durocher·Ellen Gethner
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Abstract

Scheinerman and Wilf (1994) assert that `an important open problem in the study of graph embeddings is to determine the rectilinear crossing number of the complete graph K_n.' A rectilinear drawing of K_n is an arrangement of n vertices in the plane, every pair of which is connected by an edge that is a line segment. We assume that no three vertices are collinear, and that no three edges intersect in a point unless that point is an endpoint of all three. The rectilinear crossing number of K_n is the fewest number of edge crossings attainable over all rectilinear drawings of K_n. For each n we construct a rectilinear drawing of K_n that has the fewest number of edge crossings and the best asymptotics known to date. Moreover, we give some alternative infinite families of drawings of K_n with good asymptotics. Finally, we mention some old and new open problems.

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Alex Brodsky, Stephane Durocher, Ellen Gethner. 2000-09-28. Toward the Rectilinear Crossing Number of $K_n$: New Drawings, Upper Bounds, and Asymptotics. https://doi.org/10.1016/s0012-365x(02)00491-0

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