Arima Yoriyuki Explained

was a Japanese mathematician of the Edo period. He was the lord of Kurume Domain.

He approximated the value of

\pi and its square,

\pi ^{2} . In 1766, he found the following rational approximation of \pi , correct to 29 digits:^{[1] [2]} \pi ≈ (428224593349304)/(136308121570117) =3 . 14159265358979323846264338327 ( 569 ...).

Further reading

• Book: Döll. Steffen. Hinz. Andreas M.. 2018. Kyū-renkan – the Arima sequence. Ogawa. T.. Morimoto. M.. Mathematics of Takebe Katahiro and History of Mathematics in East Asia. Advanced Studies in Pure Mathematics. 79. 321–335. Tokyo. Mathematical Society of Japan.

Notes and References

1. Web site: Collection of approximations for \pi . April 4, 2008.
2. Book: Hardy, G. H.. E. M. Wright. An Introduction to the Theory of Numbers. Oxford Science Publications. 1978.