
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 an arithmetic sequence $\{a_n\}$ with a non-zero common difference, $a_1 = 25$, and $a_1$, $a_{11}$, $a_{13}$ form a geometric sequence.

(1) Find the general formula for $\{a_n\}$.
(2) Find the sum of $a_1 + a_4 + a_7 + \ldots + a_{3n-2}$.

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