Aida Yasuaki (?? ??, February 10, 1747 – October 26, 1817) also known as Aida Ammei, was a Japanese mathematician in the Edo period.He made significant contributions to the fields of number theory and geometry, and furthered methods for simplifying continued fractions.
Aida created an original symbol for "equal".
This was the first appearance of the notation for equal in East Asia.