MathDB
Ray intersects at least k lines

Source: Nordic Mathematical Contest 2018 Problem 1

April 10, 2018
combinatoricsgeometrycombinatorial geometry

Problem Statement

Let kk be a positive integer and PP a point in the plane. We wish to draw lines, none passing through PP, in such a way that any ray starting from PP intersects at least kk of these lines. Determine the smallest number of lines needed.