Tokens and products in the board
Source: Cono Sur Math Olympiad 2020 #5
December 4, 2020
ProductsOperationInvariantscono sur
Problem Statement
There is a pile with coins on a table. At each step, Pedro choses one of the piles in the table with coins and divides it in two piles with and coins and writes in the board the product . He continues until there are piles with coin each. Determine all possible values that the final sum of the numbers in the board can have.