Pisano

Pisano is an Italian surname meaning “from Pisa.” The name is associated with people and artistic schools linked to the Italian city of Pisa, as well as with mathematical concepts named after its historic bearers.

In art and sculpture, the Pisano family refers to prominent medieval sculptors of the Pisan school, notably Nicola Pisano (circa 1225–1280) and his son Giovanni Pisano (circa 1250–1310). They were influential in the transition from Romanesque to Gothic styles, contributing extensively to public monuments, pulpit reliefs, and architectural sculpture in Italy.

In mathematics and number theory, the surname is connected to Leonardo Pisano Bigollo, better known as Fibonacci (circa 1170–1250). Fibonacci is famed for introducing Hindu-Arabic numerals to Europe in his book Liber Abaci, which helped popularize modern numbering in the Western world.

The term Pisano also appears in mathematics as the Pisano period, which describes the periodic cycle of the Fibonacci sequence modulo n. For any positive integer n, the sequence of Fibonacci numbers taken modulo n repeats after a fixed length, denoted π(n). The Pisano period is a foundational concept in modular arithmetic and has applications in algorithm design and theoretical number theory.

Overall, Pisano marks origin from Pisa and is used to identify certain historical figures in art and mathematics, as well as a specific concept in number theory derived from those historical connections.