Some records are literally irrational.
Most students are required to take a math class where they learn a few digits of pi, the irrational number which represents the ratio between a circle's circumference and its diameter. You may still remember that it starts with 3.14 (also why it’s celebrated on March 14), but with no pattern and no end, most people don’t get much beyond that. Akira Haraguchi is not most people. At a public event in 2006, he recited the number to over 100,000 digits. It took him sixteen and a half hours.
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