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CEMC Gauss (Grade 8), 2001

Number theory Difficulty 1.0 Junior Find the answer Canada

A prime number is called a “Superprime” if doubling it, and then subtracting 1, results in another prime number. The number of Superprimes less than 15 is

(A) $2$ (B) $3$ (C) $4$ (D) $5$ (E) $6$

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