Seki Takakazu

Seki Takakazu (about 1642 to 1708), also called Seki Kowa, was a mathematician, samurai and feudal officer of the early Edo period of Japan who laid the foundations for the later development of Japanese mathematics, known as wasan, and has been called Japan's Newton. He created a new algebraic notation system and, motivated by astronomical computations, worked on infinitesimals, infinite series and Diophantine equations. Little is known of his personal life, and his birth date is given anywhere from 1635 to 1643. He is credited with the discovery of Bernoulli numbers, and the resultant and the determinant are attributed to him, the first in 1683. He also calculated pi correct to the tenth decimal place using what is now called the Aitken delta-squared process. Because many results appear only in the writings of his pupils, how much of wasan is his own is uncertain, but his successors developed a school that dominated Japanese mathematics until the end of the Edo period.