
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 the coefficients of the first three terms of the expansion of $(x+ \frac {1}{2})^{n}$ form an arithmetic sequence. Let $(x+ \frac {1}{2})^{n} = a_{0} + a_{1}x + a_{2}x^{2} + \ldots + a_{n}x^{n}$. Find:  
(1) The value of $n$;  
(2) The value of $a_{5}$;  
(3) The value of $a_{0} - a_{1} + a_{2} - a_{3} + \ldots + (-1)^{n}a_{n}$.

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