
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
Let $n$ be a positive integer. Determine the function $f(n)$ if $f(1)=1$, $f(2)=3$, and

$$
2 f(n-2) + f(n-1) = f(n)
$$

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