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Depending on your philosophical views on time and calendars and so on, today is something like the 4.5 billionth Pi Day that Earth has witnessed. But that long history is nothing compared to the infinity of pi itself.

A refresher for those of you who have forgotten your seventh-grade math lessons1: Pi, or the Greek letter π, is a mathematical constant equal to the ratio of a circle’s circumference to its diameter — C/d. It lurks in every circle, and equals approximately 3.14. (Hence Pi Day, which takes place on March 14, aka 3/14.)

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A refresher for those of you who have forgotten your seventh-grade math lessons1: Pi, or the Greek letter π, is a mathematical constant equal to the ratio of a circle’s circumference to its diameter — C/d. It lurks in every circle, and equals approximately 3.14. (Hence Pi Day, which takes place on March 14, aka 3/14.)

9 weeks ago by rgl7194