MathDB
Putnam 1968 A4

Source: Putnam 1968

February 19, 2022
Putnamgeometry3D geometrysphere

Problem Statement

Let S2R3S^{2}\subset \mathbb{R}^{3} be the unit sphere. Show that for any nn points on S2 S^{2}, the sum of the squares of the n(n1)2\frac{n(n-1)}{2} distances between them is at most n2n^{2}.