
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
Let $a_n$ ($n=2,3,4,\ldots$) be the coefficient of the linear term in $x$ in the expansion of $(3- \sqrt{x})^n$. The value of $$\frac { \frac {a_{2}}{3^{2}}+ \frac {a_{3}}{3^{3}}+…+ \frac {a_{2015}}{3^{2015}}}{ A_{ 2016 }^{ 3 }}$$ is \_\_\_\_\_\_.

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