The Digits of Pi

13. Pi in the Sky

The Digits of Pi

The pie-eating Digits (see "Pi in the Sky") are seated in the same order as the digits of a mysterious and special number in mathematics known as pi.

Pi is the ratio of a circle's circumference (the distance around the circle) to its diameter (the distance across, passing through the center). No matter how large or small the circle, the circumference divided by the diameter equals 3.14159265…: the number we call pi.

The digits of pi on a plaque at the Exploratorium in San Francisco.

The digits to the right of the decimal point continue without end, following no particular pattern. The mathematical symbol for pi is the Greek letter "𝛑."

Because pi is an irrational number, it can't be expressed exactly as a fraction, such as 3/4 or 22/7. It would take an infinite sequence of decimal digits to state the number exactly. So if all the Digits representing the digits of pi were lined up along the bench of a picnic table, the table would have to be infinitely long.

The "current population" (as of the year 2020) of alien Digits, however, is only 50 trillion. That's the number of consecutive digits of pi that anyone has calculated so far.

See also "A Passion for Pi."

NEXT: Digit Hunters