
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given that the positive term geometric sequence ${a_n}$ satisfies $a_n a_{n+1} = 4^n$ ($n \in \mathbb{N}^*$).
1. Find the general term formula of the sequence ${a_n}$.
2. Let $b_n = \frac{1}{\log_2 a_n \log_2 a_{n+1}}$, find the sum of the first $n$ terms $S_n$ of the sequence ${b_n}$.

Present the answer in LaTex format: \boxed{Your answer}
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