Re: Happy Pi Day!
The historically first exact formula for π, based on infinite series, was not available until a millennium later, when in the 14th century the Madhava–Leibniz series was discovered in Indian mathematics.[1][2] In the 20th and 21st centuries, mathematicians and computer scientists discovered new approaches that, when combined with increasing computational power, extended the decimal representation of π to, as of late 2013, over 13.3 trillion (1013) digits.[3]
"Round 2... 10 Trillion Digits of Pi", NumberWorld.org, 17 Oct 2011. Retrieved 30 May 2012.
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