
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 ${a_n}$ is a geometric sequence, $a_1=2$, and $a_1$, $a_3+1$, $a_4$ form an arithmetic sequence.
(1) Find the general term formula for the sequence ${a_n}$;
(2) If $b_n=(2n-1) \cdot a_n$, find the sum of the first $n$ terms, $S_n$, of the sequence ${b_n}$.

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