koru The koru (Māori for "loop") is a spiral shape based on the shape of a new unfurling silver fern frond and symbolizing new life, growth, strength and peace. It is an integral symbol in Māori art, carving and tattoos. The circular shape of the koru helps to convey the idea of perpetual movement while the inner coil suggests a return to the point of origin.
Integral symbol The ∫ symbol is used to denote the integral in mathematics. The notation was introduced by the German mathematician Gottfried Wilhelm von Leibniz towards the end of the 17th century. The symbol was based on the ſ (long s) character, and was chosen because Leibniz thought of the integral as an infinite sum of infinitesimal summands.