
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 Fengtai District Preliminary Exam of 2011, all positive odd numbers are arranged into a triangular array:

$$
\begin{align*}
&1\\
&3\ \ 5\\
&7\ \ 9\ \ 11\\
&13\ 15\ 17\ 19\\
&...
\end{align*}
$$

Following the pattern of arrangement above, the third number from the left in the nth row (where $n \geq 3$) is what?

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