# Legendre symbol

> English word · Noun

## Definitions
1. A mathematical function of an integer and a prime number, written (a/p), which indicates whether a is a quadratic residue modulo p.

## Etymology
Named after French mathematician Adrien-Marie Legendre (1752–1833), who introduced the symbol in 1798 in his work Essai sur la Théorie des Nombres ("Essay on the Theory of Numbers").

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/legendre-symbol