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All About Pi
Math nerds everywhere are digging into a slice of pecan pie today to celebrate their most iconic irrational number: pi. After all, March 14, or 3/14, is the perfect time to honor the essential mathematical constant, whose first digits are 3.14.
Pi, or π, is the ratio of a circle's circumference to its diameter. Because it is irrational, it can't be written as a fraction. Instead, it is an infinitely long, nonrepeating number.
But how was this irrational number discovered, and after thousands of years of being studied, does this number still have any secrets? From the number's ancient origins to its murky future, here are some of the most surprising facts about pi. [The 9 Most Massive Numbers in Existence]

Memorizing pi
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Memorizing pi
The record for the most digits of pi memorized belongs to Rajveer Meena of Vellore, India, who recited 70,000 decimal places of pi on March 21, 2015, according to Guinness World Records. Previously, Chao Lu, of China, who recited pi from memory to 67,890 places in 2005, held the record, according to Guinness World Records.
The unofficial record holder is Akira Haraguchi, who videotaped a performance of his recitation of 100,000 decimal places of pi in 2005, and more recently topped 117,000 decimal places, the Guardian reported.
Number enthusiasts have memorized many digits of pi. Many people use memory aids, such as mnemonic techniques known as piphilology, to help them remember. Often, they use poems written in Pilish (in which the number of letters in each word corresponds to a digit of pi), such as this excerpt:
How I want a drink, alcoholic of course, after the heavy lectures involving quantum mechanics.
Now I fall, a tired suburbian in liquid under the trees,
Drifting alongside forests simmering red in the twilight over Europe.
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There's a pi "language"
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There's a pi "language"
Literary nerds invented a dialect known as Pilish, in which the numbers of letters in successive words match the digits of pi. For example, Mike Keith wrote the book "Not A Wake" (Vinculum Press, 2010) entirely in Pilish:
Now I fall, a tired suburbian in liquid under the trees,
Drifting alongside forests simmering red in the twilight over Europe.("Now" has three letters, "I" has one letter, "fall" has four letters, and so on.)
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Exponential increase
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Exponential increase
Because pi is an infinite number, humans will, by definition, never determine every single digit of pi. However, the number of decimal places calculated has grown exponentially since pi's first use. The Babylonians thought the fraction 3 1/8 was good enough in 2000 B.C., while the ancient Chinese and the writers of the Old Testament (Kings 7:23) seemed perfectly happy to use the integer 3. But by 1665, Sir Isaac Newton had calculated pi to 16 decimal places. By 1719, French mathematician Thomas Fantet de Lagny had calculated 127 decimal places, according to "A History of Pi" (St. Martin's Press, 1976). [The Most Massive Numbers in Existence]
The advent of computers radically improved humans' knowledge of pi. Between 1949 and 1967, the number of known decimal places of pi skyrocketed from 2,037 on the ENIAC computer to 500,000 on the CDC 6600 in Paris, according to "A History of Pi" (St. Martin's Press, 1976). And late last year, Peter Trueb, a scientist at the Swiss company Dectris Ltd., used a multithreaded computer program to calculate 22,459,157,718,361 digits of pi over the course of 105 days, according to the group.
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Handcalculating pi
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