
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
In the arithmetic sequence {a<sub>n</sub>}, a<sub>5</sub> = 4, a<sub>3</sub> + a<sub>8</sub> = 9.
(1) Find the general term formula for {a<sub>n</sub>};
(2) Let b<sub>n</sub> = 2a<sub>n</sub> - 1, find the sum of the first n terms S<sub>n</sub> for the sequence {b<sub>n</sub>}.

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