Question 71
a. Find all perfect squares of the form $aabcc$.
b. Let $n$ be a given positive integer. Prove that there exists a perfect square of the form $aab \underbrace{cc\dots c}_{2n \text{ times}}$.
b. Let $n$ be a given positive integer. Prove that there exists a perfect square of the form $aab \underbrace{cc\dots c}_{2n \text{ times}}$.