
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
Guess the number. Sixth graders Petya, Vasya, Kolya, and Anton made the following statements:
- Petya: "The number is prime."
- Vasya: "The number is 9."
- Kolya: "The number is even."
- Anton: "The number is 15."

It is known that exactly one of Petya’s and Vasya’s statements is true, and exactly one of Kolya’s and Anton’s statements is true. What is the number?

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