For how many positive integer values of $n$ is $3^n$ a factor of $15!$?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
For how many positive integer values of $n$ is $3^n$ a factor of $15!$?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
6
For how many positive integer values of $n$ is $3^n$ a factor of $15!$?
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