Pi Day (March 14) is a day of global mathematical celebration, but it’s not the only numerically significant calendar date. It’s far from the rarest, either. In fact, today marks a special occasion ...

Pythagorean Triple Square Day, as one man affectionately calls 9/16/25, is a day like no other this century. On 9/16/25, celebrate a date of mathematical beauty Once a century, a very special day ...

But perhaps most special of all is that three, four, and five are an example of what's called a Pythagorean triple. It's a theorem that means something geometrically, too. Any Pythagorean triple — ...

Once a century, a very special day comes along. That day is today — 9/16/25. Pi Day (3/14) often comes with sweet treats; Square Root Day (4/4/16 or 5/5/25, for example) has a certain numerical rhyme.

For centuries, students have learned that in a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides. Known as the Pythagorean Theorem, this ...

This is an updated version of a story first published on May 5, 2024. For many high school students returning to class, it may seem like geometry and trigonometry were created by the Greeks as a form ...