
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
In the sequence $\{a\_n\}$, $a\_1=2$, $a\_2=8$, and for all positive integers $n$, $a_{n+2}+a_{n}=a_{n+1}$. Find the sum $\sum\limits_{n-1}^{2017}a_{n}=$ \_\_\_\_\_\_.

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