
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 a sequence $\{a_n\}$ that satisfies the recurrence relation $a_n = a_{n-1} + a_{n-2}$ for $n > 2$, $n \in \mathbb{N}^*$, and given $a_{2015} = 1$ and $a_{2017} = -1$, calculate the value of $S_{2020} - S_{2016}$.

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