Arithmetica

Arithmetica (Greek: Ἀριθμητικά) is an Ancient Greek text on mathematics written by the mathematician Diophantus in the 3rd century AD. It is a collection of 130 algebraic problems giving numerical solutions of determinate equations (those with a unique solution) and indeterminate equations.

Equations in the book are called Diophantine equations. The method for solving these equations is known as Diophantine analysis. Most of the Arithmetica problems lead to quadratic equations. It was these equations which inspired Pierre de Fermat to propose Fermat's Last Theorem, scrawled in the margins of Fermat's copy of Arithmetica, which states that the equation ${\displaystyle x^{n}+y^{n}=z^{n}}$, where ${\displaystyle x}$, ${\displaystyle y}$, ${\displaystyle z}$ and ${\displaystyle n}$ are non-zero integers, has no solution with ${\displaystyle n}$ greater than 2.

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