Question 4
Find all natural numbers $a,b$ such that
$$a\mid b^2,\quad b\mid a^2,\quad\text{and}\quad a+1\mid b^2+1.$$
$$a\mid b^2,\quad b\mid a^2,\quad\text{and}\quad a+1\mid b^2+1.$$
MathNet 2012 Question 4
Math Olympiad Vault · MathNet 2012
Math Olympiad Vault · MathNet 2012