MathDB
cyclic shifts

Source: All-Russian olympiad 1995, Grade 11, Second Day, Problem 6

October 21, 2013
combinatorics proposedcombinatorics

Problem Statement

A boy goes nn times at a merry-go-round with nn seats. After every time he moves in the clockwise direction and takes another seat, not making a full circle. The number of seats he passes by at each move is called the length of the move. For which nn can he sit at every seat, if the lengths of all the nāˆ’1n-1 moves he makes have different lengths? V. New