Xu Yue

Xu Yue

(born c. 185, Donglai, China—died c. 227, China) Chinese astronomer and mathematician. He wrote several books, of which only Shushu jiyi (“Memoir on the Methods of Numbering”) is extant; some scholars question its authenticity. The treatise was used as an auxiliary mathematics textbook in the Tang (618–907) and Song (960–1279) state universities. Its first part provides three methods of assigning the powers of 10 up to 10^4,096 to traditionally established terms for “large numbers” and alludes to a method of indefinite generation of even larger numbers. The second part contains descriptions of various devices for representing, if not actually manipulating, large numbers. Among them the book mentions a device resembling the abacus, which some scholars believe originated in China.