1. The problem statement, all variables and given/known data Let n be any odd integer. Prove that 1 is the only "common" divisor of the integers n and n+2. 3. The attempt at a solution I don't think I understand the question. The few notes I have state d| (n+2 )- n This resembles n+2 ##\equiv## n mod d , but I don't see the connection. The congruency means that n+2 and n share the same remainder. Any help?