Diophatus of Alexandria.

Diophantus of Alexandria (Greek: Διόφαντος ὁ Ἀλεξανδρεύς. b. between 200 and 214 CE, d. between 284 and 298 CE), sometimes called "the father of algebra", was an Alexandrian Greek mathematician and the author of a series of books called Arithmetica. These texts deal with solving algebraic equations, many of which are now lost.