
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 the sequence $\{a_n\}$ with the general term formula $a_n = 2n - 3$, the terms of the sequence are grouped as follows: the first group contains 1 number ($a_1$), the second group contains 2 numbers ($a_2$, $a_3$), the third group contains 3 numbers ($a_4$, $a_5$, $a_6$), and so on. What is the 10th number in the 16th group?

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