
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
The ancient Greek mathematicians defined polygonal numbers based on natural numbers in the following way:
- Triangular numbers: 1, 3, 6, 10, 15, ...
- Square numbers: 1, 4, 9, 16, 25, ...
- Pentagonal numbers: 1, 5, 12, 22, 35, ...
- Hexagonal numbers: 1, 6, 15, 28, 45, ...

According to the above sequence, what is the 8th hexagonal number? ( )

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