A whole number is written on a piece of paper.
You are given three clues to help you work out the number written on the piece
of paper.
Clue 1: Triple the number is between 18 and 33 inclusive.
Clue 2: The number is a prime number.
Clue 3: The number is not a factor of 99.
Use each of the clues above to refine your search.
Enter the list of numbers obtained after each clue to finally find the number
written on the piece of paper.
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