MathDB
2019 point grasshoppers sit on a line, jumping around

Source: Tournament of Towns, Junior A-Level , Spring 2019 p2

May 9, 2020
Linegamegame strategycombinatoricsTournament of TownsToTKvant

Problem Statement

20192019 point grasshoppers sit on a line. At each move one of the grasshoppers jumps over another one and lands at the point the same distance away from it. Jumping only to the right, the grasshoppers are able to position themselves so that some two of them are exactly 11 mm apart. Prove that the grasshoppers can achieve the same, jumping only to the left and starting from the initial position.
(Sergey Dorichenko)