Kara, Jan
Big Line or Big Clique in Planar Point Sets ★★
Let be a set of points in the plane. Two points and in are visible with respect to if the line segment between and contains no other point in .
Conjecture For all integers there is an integer such that every set of at least points in the plane contains at least collinear points or pairwise visible points.
Keywords: Discrete Geometry; Geometric Ramsey Theory