
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 the sequence $\{a_n\}$ with the sum of the first $n$ terms $S_n=1-5+9-13+\ldots+(-1)^{n-1}(4n-3)$, find the value of $S_{15}+S_{22}-S_{31}$.

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