Floral spiral patterns. Artwork showing the mathematical relationship between repeating spirals in a floral pattern. Many floral patterns repeat themselves following the Fibonacci sequence of numbers (1,2,3,5,8,13,21 etc). The ratio between two Fibonacci numbers is known as Phi (1.618). In some sequences, the spirals form a pattern known as Fermat's spirals (upper left, lower right) which can be seen in many patterns in nature such as the florets on a sunflower head or on the scales of a pine cone.