Maths Olympiad Prep

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Problem 65

Number theory Difficulty 1.0 Find the answer UKMT Senior Mathematical Challenge · United Kingdom · 2016

Which of the following values of the positive integer nn is a counterexample to the statement: "If nn is not prime then n2n - 2 is not prime"?

(A) 66 (B) 1111 (C) 2727 (D) 3333 (E) 5151

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