MathDB

n

people sitting at a round table. In the beginning, everyone writes down a positive number

n

on piece of paper in front of them. From now on, in every minute, they write down the number that they get if they subtract the number of their right-hand neighbour from their own number. They write down the new number and erase the original. Give those number

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that there exists an integer

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in a way that regardless of the starting numbers, after

k

minutes, everyone will have a number that is divisible by

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Problem Statement