Tuesday, November 24, 2009

Fibonacci Sequence

History of the Fibonacci Sequence

the Fibonacci Sequence is a series of numbers in which each succeding number is the sum of the previous two.

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

Leonardo Pisano, an Italian mathmatician, is the founder of the Fibonacci Sequence. He grew up in North Africa and was educated by Moors. He travelled frequently amoung merchants, learning their systems of arithmetic. He felt that the most effective one he found was the "Hindu-Arabic" system. He is credited with introducing this system to Europe in his book, Liber Abaci. Within this book he explains numerous mathmatical subjects. The most famous part of this book is the third section. He poses the question about the reproduction rate of rabbits. In this sections the series of number is discoverd.


Explanation of rabbit reproduction: You start out with 0 rabits in a cage. Add 1 rabbit, then add 1 more of the opposite gender. Now you have 2 rabbits, which is the fourth number of the Fibonacci Sequence. The rabbits mate, and have one baby rabbit. Now there is a total of 3 rabbits in the cage!


Another of example of the Fibonacci Sequence in Nature.


The memebers of the plant family, Asteraceae, have a Fibonacci Sequence of petals. A common flower of this family is the Daisy. A Daisy can have a total number of 34, 55, or 89 petals.



The Fibonacci Spiral can be seen numerous times in nature. The shells of snails show this spiral.




It starts out with 1 1x1 box, than add another 1x1 box. One plus one equals two, so draw a 2x2 box. Now this is a total of 3 boxs. The fouth box will be 3x3. The sequence continues the same way.


The Fibonnaci Sequence isn't only seen in nature, it is in Music, too.



Look at a Piano. One octave on a piano has 13 keys; 8 are white and 5 are black. Of those 5 black keys, they are divided into two groups of 3 and 2 keys. And those 8 white keys can be divided into two groups of 3 and 5 white keys! ( btw, I never realized this before researching it- this is so awesome)

Some examples of the Fibonacci Sequence can be seen and heard in the musical compositions of a few composers.

In a song called Lateralus, by Tool; this band clearly uses the Fibonacci Sequence in his lyrics.


Here is a video that explains it all:


I couldn't upload this video :(

It's really cool though.