Prime Sets
Lin wrote all numbers of the form $ p_1^x \cdot p_2^y $ in the notebook, where $ p_1 $ and $ p_2 $ are different primes, and $ x $ and $ y $ are non-negative integers not exceeding 5. After that, he circled some and got some set $ A $. How many different sets $ A $ exist for which for any $ n \in A $ it is known that $ m \in A $ if $ m | n $ and $ m \in N $.
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