## 30 March 2017

### Fibonacci sequence

The Fibonacci sequence characterized by the fact that every number after the first two is the sum of the two preceding ones:

$1,\,1,\,2,\,3,\,5,\,8,\,13,\,21,\,34,\,55,\,89,\,144,\, \cdots$

The Fibonacci sequence is named after Italian mathematician Leonardo of Pisa, known as Fibonacci, that have introduced the sequence to Western European mathematics.

Fibonacci sequences appear in nature, such as branching in trees, arrangement of leaves on a stem, the fruitlets of a pineapple, the flowering of artichoke, an uncurling fern and the arrangement of a pine cone and the family tree of honeybees.