Question 143
Let $p$ be an odd prime number. Find all natural numbers $k$ such that
$$
\sqrt{k^{2}-p k}
$$
is a positive integer.
$$
\sqrt{k^{2}-p k}
$$
is a positive integer.
MathNet 2004 — Part 01 Question 143
Math Olympiad Vault · MathNet 2004 — Part 01