
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
Observe the following equations:
$$
\begin{array}{l}
1+3=4=2 \times 2 \\
1+3+5=9=3 \times 3 \\
1+3+5+7=16=4 \times 4 .
\end{array}
$$

Calculate: $1+3+5+\cdots+2019=$ $\qquad$

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