The sequence of natural numbers satisfies for all . Prove that
Can anyone show me a full solution to this question? (I'm quite noob at number theory since I just started it, please don't leave out any steps!!)
The number 2 has the property that GCD(2,j) = 1 or 2 for all j, and it is the only number with that property. Therefore .
Can you continue that line of reasoning?