Terms used in number theory, the branch of mathematics concerned with properties of the integers.
Jacobi symbol - (a/p), where p is an odd prime, and a is an integer. If GCD(a,p)≠1 then (a/p)=0. Otherwise, (a/p)=1 if a is a quadratic residue (mod p), and (a/p)=-1 if a is a quadratic non-residue (mod p).
pairwise coprime - a set of integers is pairwise coprime if no two elements of the set share any factor other than 1 or -1. (Note: 1 is coprime to every integer by this definition.)
quadratic residue - a square, modulo some number. A number, n, is said to be a quadratic residue (mod p) if k2=n (mod p) for some integer, k.
quadratic non-residue - a non-square, modulo some number. If n is not a quadratic residue (mod p), then n is a quadratic non-residue (mod p). It's a bit of an odd expression, since a residue (mod p) of a number, n, is the remainder upon division of n by p. If it happens that n isn't the square of any number, that doesn't make n a non-residue, but perhaps non-quadratic.
Other glossaries: Geometry Glossary, Statistics Glossary, Topology Glossary
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