👉 In mathematics, "sylvan" is a term used to describe a set of points in a plane or space that are symmetric with respect to a given axis. The term is named after the mathematician and physicist János Selye, who first introduced it in 1904. Sylvans are often used in geometry and topology to define certain geometric objects such as cones, spheres, and cylinders. They can be thought of as points that lie on or below a given
