Squarefree Numbers
Public  1w:6d  7xp  Math  75.0% 
A Squarefree number is a number not divisible by a perfect square (other than 1).
How many squarefree numbers $ \le 123456789123456789 $ are there?
Answer format: count
[My timing: 55 sec]
How many squarefree numbers $ \le 123456789123456789 $ are there?
Answer format: count
[My timing: 55 sec]
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