Pi, a mathematical constant denoted by the Greek letter π, is the ratio of a circle's circumference C to its diameter d: π = C/d. The circumference of a circle is, in turn, equal to 2πr, where r is ...

March 14, 2018, is Pi Day — that’s pi, not pie — and on Wednesday, Google marks the 30th anniversary of the math-inspired holiday with a special Doodle. Pi, denoted by the Greek letter “π”, has been ...

For centuries, Pi was thought to be an unchanging constant defined by the circle. Recent mathematical advances have revealed ...

The decades have been good to Pi. Its happy swirl of Jewish mysticism, meaning-of-everything conspiracism, and Math’s Greatest Hits (along with pi, it bangs through the Fibonnaci sequence, the golden ...

Today is Pi Day, an annual celebration of the famous mathematical concept that has fascinated people for millenia. But what exactly is π (pronounced like the word "pie"), and where did the concept ...