👉 Cinclides is a mathematical concept in number theory that refers to the set of numbers which are relatively prime (i.e., their greatest common divisor with each other is 1). This means that if a and b are relatively prime, then gcd(a,b) = 1. For example, 3 and 5 are relatively prime because gcd(3,5)=1. Cinclides play an important role in number theory as they can be used to find the greatest common divisor