👉 In mathematics, "beltian" is a mathematical concept that refers to the ratio of the circumference of a circle to its diameter. It can also be defined as the area of a circle divided by its radius squared (A = πr²). The ratio between these two quantities represents the proportionality between the size of an object and its distance from the center, or in other words, it is the "radius-to-diameter" relationship. This concept has many applications in various fields such as geometry