# Square Triangles

**Number Theory**Level 1

What is the smallest positive integer greater than \(1\) that is both a triangular number and a perfect square?

**Note:** A triangular number is a number which can be expressed as a sum of the first \(n\) positive integers, such as \(6 = 1+2+3\) or \(15 = 1+2+3+4+5\).