
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 \( a_{n} = \frac{n(n+1)}{2} \). From the sequence \(\left\{a_{n}\right\}\), remove all numbers that are divisible by 3. Then the remaining terms are rearranged in ascending order to form the sequence \(\left\{b_{n}\right\}\). Find the value of \( b_{200} \).

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