# Latest Numerical approximations of π Stories

In his 1989 book "The Emperor's New Mind", Roger Penrose commented on the limitations on human knowledge with a striking example: He conjectured that we would most likely never know whether a string of 10 consecutive 7s appears in the digital expansion of the number pi.

A researcher working for technology firm Yahoo has calculated the 2,000,000,000,000,000th digit of pi, more than doubling the previous record.

Japanese and US computer whizzes say they have calculated pi to five trillion decimal places, which is a number that could beat a previous record set by a French software engineer if verified.

Computer scientist Fabrice Bellard said he has computed the mathematical constant pi to nearly 2.7 trillion digits, some 123 billion more than the previous record.

On Tuesday, math lovers across the country are celebrating national Square Root Day, a holiday that comes around only when the day and the month are both the square root of the last two digits of the current year.

A high school student Tuesday recited 8,784 digits of Pi - the non-repeating and non-terminating decimal - likely placing him among the top Pi-reciters in the world.

If you wanted a random number, historically you could do worse than to pick a sequence from the string of digits in pi. But Purdue University scientists now say other sources might be better.

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