MathDB
Chisinau MO p58 1949-56 X no of lines, m points out of n points

Source:

March 15, 2021
geometrycombinatorial geometrycombinatoricspointslines

Problem Statement

On the plane nn points are chosen so that exactly mm of them lie on one straight line and no three points not included in these mm points lie on one straight line. What is the number of all lines, each of which contains at least two of these points?