The sum of the first odd numbers is a square number,
A sort of converse also exists, namely the difference of the th and st square numbers is the th odd number, which follows from
The sum of the first odd numbers is a square number,
A sort of converse also exists, namely the difference of the th and st square numbers is the th odd number, which follows from
Weisstein, Eric W. "Odd Number Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/OddNumberTheorem.html