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Let m, n be integers. We say that m and n are coprime numbers (or relatively prime) if there exists no integer larger than 1 which divides both n and m. Example: 4 and 9 are coprime, 13 and 91 are not (91 is divisible by 13). Prove that if you choose 31 integers from the range of number within [1, 2, 3 . . . , 60], that at least two numbers must be coprime