
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 first term $a\_1 = 1$ and the property $a_{n+1} - a_n = (- \frac{1}{2})^n$, find the value of $a_{2018}$.
A) $1 - (\frac{1}{2})^{2017}$
B) $2 - (\frac{1}{2})^{2017}$
C) $\frac{2[1 - (\frac{1}{2})^{2018}]}{3}$
D) $\frac{2[1 - (\frac{1}{2})^{2017}]}{3}$

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