It is a set of numbers in which each number from third onwards is obtained by adding the previous two. Any sequence which obeys this rule is a Fibonacci Sequence, no matter what the first two numbers are: 1,1,2,3,5,8,13, 21, 34, …… or 4,7,11, 18, 29, ….
What’s the specialty about this sequence?
The numbers…. and Fibonacci ratio, which is the ratio of two successive terms in Fibonacci Sequence. This is the first, recursive number sequence known in Europe in which the ration between the two or more successive terms can be expressed by a formula. This fascinating and interesting sequence was given by Leonardo Fibonacci when he was just 22. But the term “Fibonacci Sequence” was coined in 19th century by a French mathematician Edward Lucas. Thereafter scientists began to discover the numbers of this sequence in nature. As a simple example, next time, if you pick up a sunflower head and count spirals, you’ll observe that the head has 55 spirals in the clockwise and 34 in anti-clockwise direction. Look at a pine cone which has 13 anti-clockwise and 8 clockwise parts, both follow Fibonacci ratio numbers from this sequence arise in many surprising contexts including the structure of bee-hive, the population of a rabbit warren, white-black notes on a piano keyboard. Not only this, many growth processes in nature govern the sequence.