Question 2
1) Let a,b be real numbers such that $a^n+b^n$ is an integer for n=1,2,3,4. Prove it is an integer for every $n\in\mathbb N^*$.
2) Is it true that if a,b are real and $a^n+b^n$ is an integer for n=1,2,3, then it is an integer for every $n\in\mathbb N^*$?
2) Is it true that if a,b are real and $a^n+b^n$ is an integer for n=1,2,3, then it is an integer for every $n\in\mathbb N^*$?