Fibonacci numbers in mathematics, are the numbers making up a series of numbers called the Fibonacci sequence. The sequence is characterized by the fact that every number after the first two, is the sum of the two preceding ones.

Simply put, the Fibonacci sequence goes like this-

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, ……

The first two numbers can be either 1 and 1 or 0 and 1, depending on the selected starting point of the sequence.

Fibonacci numbers are named after the Italian mathematician Leonardo Pisano Bogollo, whose nickname was Fibonacci. Loosely translated, Fibonacci means ‘Son of Bonacci’. But it was in India that the numbers were appeared to have been first seen. They were discovered as early as 200 BC in the work of Pingala, India’s ancient mathematician who authored the earliest known Sanskrit prosody, Chandahsastra. In this Sanskrit poetic work was seen this interest of enumerating all the patterns of long syllables of 2 units duration, contrasted with short syllables of 1 unit duration. Counting the pattern of the long and short syllables resulted in the Fibonacci numbers.

However, the clearest exposition of the Fibonacci sequence can be seen in the work of Virahanka, the 6th century Indian mathematician and prosodist. Thus developed by early Indian mathematicians, the Fibonacci sequence was later on discussed independently by Italian and German mathematicians like Fibonacci and Johannes Kepler.

Today, Fibonacci numbers appear so often in mathematics that an entire journal called Fibonacci Quarterly is dedicated to their study. The numbers are applied in computer algorithms and biological settings like branching in trees, fruit sprouts in pineapple, phyllotaxis, the flowering of an artichoke and several others.

Based on the Fibonacci sequence, “1, 1, 2, 3”, 11/23 or November 23rd is named as Fibonacci Day!