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2022 Alg/NT DIv 1 P5

Source:

February 28, 2022
algebranumber theory

Problem Statement

Grant is standing at the beginning of a hallway with infinitely many lockers, numbered, 1,2,3,1, 2, 3, \ldots All of the lockers are initially closed. Initially, he has some set S={1,2,3,}S = \{1, 2, 3, \ldots\}.
Every step, for each element ss of SS, Grant goes through the hallway and opens each locker divisible by ss that is closed, and closes each locker divisible by ss that is open. Once he does this for all ss, he then replaces SS with the set of labels of the currently open lockers, and then closes every door again.
After 20222022 steps, SS has nn integers that divide 102022{10}^{2022}. Find nn.
Proposed by Oliver Hayman