Problem #PRU-100669

Problems Methods Invariants and semi-invariants Invariants

Problem

There are numbers \(1,2,3,4,5,6,7,8,9\) and \(10\) written on a board. Each time you make a “move” you can erase three of the remaining numbers, \(a,b\) and \(c\), and replace them with the numbers \(2a+b\), \(2b+c\) and \(2c+b\). The goal is to make all the \(10\) numbers left on the board equal. Is it possible?