MathDB
writing numbers around circle, minimal sum

Source: VJIMC 2002 1.4

July 17, 2021
inequalities

Problem Statement

The numbers 1,2,,n1,2,\ldots,n are assigned to the vertices of a regular nn-gon in an arbitrary order. For each edge, compute the product of the two numbers at the endpoints and sum up these products. What is the smallest possible value of this sum?