Diophantus

Diophantus of Alexandria was a Greek mathematician active in the 3rd century AD, known chiefly for his Arithmetica, a collection of 290 algebraic problems that give numerical solutions to determinate and indeterminate equations. Although Joseph-Louis Lagrange later called him the inventor of algebra, Diophantus did not create the discipline outright but developed systematic methods for solving arithmetic problems through algebraic technique, work that influenced mathematicians from the medieval Islamic world through Renaissance Europe. His name remains attached to the class of problems now called Diophantine equations and to the field of Diophantine analysis.