MathDB
x_1 +k/x_2=x_2 +k/x_3=...=x_n +k/x_1

Source: 2019 Dürer Math Competition Finals Day2 E13 https://artofproblemsolving.com/community/c1621835_2019_

January 5, 2022
algebrasystem of equationsnumber theorySystem

Problem Statement

Let k>1k > 1 be a positive integer and n2019n \ge 2019 be an odd positive integer. The non-zero rational numbers x1,x2,...,xnx_1, x_2,..., x_n are not all equal, and satisfy the following chain of equalities: x1+kx2=x2+kx3=x3+kx4=...=xn1+kxn=xn+kx1.x_1 +\frac{k}{x_2}= x_2 +\frac{k}{x_3}= x_3 +\frac{k}{x_4}= ... = x_{n-1} +\frac{k}{x_n}= x_n +\frac{k}{x_1}. What is the smallest possible value of kk?