Maths Olympiad Prep

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Number theory Difficulty 5.3 AIME, harder Prove it Netherlands

One hundred brownies (girl scouts) are sitting in a big circle around the camp fire. Each brownie has one or more chestnuts and no two brownies have the same number of chestnuts. Each brownie divides her number of chestnuts by the number of chestnuts of her right neighbour and writes down the remainder on a green piece of paper. Each brownie also divides her number by the number of chestnuts of her left neighbour and writes down the remainder on a red piece of paper. For example, if Anja has 2323 chestnuts and her right neighbour Bregje has 55, then Anja writes 33 on her green piece of paper and Bregje writes 55 on her red piece of paper.

If the number of distinct remainders on the 100100 green pieces of paper equals 22, what is the smallest possible number of distinct remainders on the 100100 red pieces of paper?

Solution

100100

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