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UKMT Junior Mathematical Challenge, 2023

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

How many of these six numbers are prime? $0^2+1^2$ , $1^2+2^2$ , $2^2+3^2$ , $3^2+4^2$ , $4^2+5^2$ , $5^2+6^2$

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

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