Let P be a 2019āgon, such that no three of its diagonals concur at an internal point. We will call each internal intersection point of diagonals of P a knot. What is the greatest number of knots one can choose, such that there doesn't exist a cycle of chosen knots? ( Every two adjacent knots in a cycle must be on the same diagonal and on every diagonal there are at most two knots from a cycle.) combinatoricscombinatorial geometrygeometry