Problem #PRU-116873

Problemas Métodos Principio extremal Principio extremal (otro) Inducción matemática Inducción matemática (otro) Métodos algebraicos Particiones en pares y grupos; biyecciones Principio del casillero Principio del casillero (otro)
 14–15  4.0

Problem

We are given \(n+1\) different natural numbers, which are less than \(2n\) (\(n>1\)). Prove that among them there will always be three numbers, where the sum of two of them is equal to the third.