# The Lockers

Number Theory Level 3

Lockers numbered $$1$$ to $$10000$$ stand in a row in the gym. When the first student, he opens all lockers. The second student change the state of every locker that is a multiple of $$2$$ and in general, the $$n$$-th student changes the state of a locker that is numbered a multiple of $$n$$.

After $$10000$$ passes through, how many lockers are closed?

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