
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 that n is a natural number, evaluate the expression C_{n}^{0}2n-C_{n}^{1}2n-1+...+(-1)^{k}C_{n}^{k}2n-k+...+(-1)^{n}C_{n}^{n}.

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