## 3-14-15 9:26:53.

That sequence of numbers only comes around every 100 years. For those not mathematically inclined, the numbers represent the ratio of Pi. On Saturday, March 14, math aficionados the world over will celebrate this unique day.

Pi is the number of copies of the diameter that you need to measure out the circumference of a circle. Pi has been calculated to over one trillion digits beyond its decimal point. While we can’t duplicate that incredible sum, we did our best to capture all the circles on campus in the above photo gallery.

### History of Pi

Anything that involves circles almost inevitably also involves this ratio. The earliest recorded use was in the Rhind papyrus from the Egyptian Middle Kingdom, around 1650 BCE.

Today we find it used in astronomy and rocket trajectories, in modeling biological rhythms or any periodic phenomena, and in almost everything that involves wheels or curves. There are also less obvious connections to circles. Pi appears in the formula for the Gaussian distribution, one of the foundational formulas of statistical analysis. While this ratio was well known and studied since ancient times throughout the world, the use of the greek letter pi did not come about until the 1700s whenÂ Leonhard Euler popularized this short-hand. He used the greek letter for “p,” standing for “perimetros” or “perimeter.”

March 11 2015