Modular Arithmetic

Mod, modular inverse, and properties

17 mod 5 · a⁻¹ such that a · a⁻¹ ≡ 1 (mod 5)

a mod m

Least non-negative residue, in the range 0 to m − 1

gcd(a, m)

Coprime

Yes — a is invertible modulo m

Modular inverse a⁻¹ (mod m)

a · a⁻¹ ≡ 1 (mod m)

Bézout identity

17·(-2) + 5·(7) = 1