Yoriyuki Arima
Encyclopedia
was a Japan
ese mathematician
of the Edo period
. He was the lord of Kurume Domain
and approximated the value of
and its square, 
. In 1766, he found the following rational approximation of pi, correct to 29 digits:
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese mathematician
Mathematician
A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....
of the Edo period
Edo period
The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....
. He was the lord of Kurume Domain
Kurume Domain
The ' was a Japanese domain of the Edo period, ruled by the Arima clan. It was located in Chikugo Province .The Arima clan became viscounts in the Meiji era.-List of lords:* Arima clan 1620-1871...
and approximated the value of
and its square, . In 1766, he found the following rational approximation of pi, correct to 29 digits: