# Fibonacci (work in progress)

The Fibonacci numbers form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1. So: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144 and so on.

In his 1202 book Liber Abaci, Fibonacci (the Italian mathematician Leonardo of Pisa) introduced the sequence to Western European mathematics. The sequence had been described earlier in Indian mathematics, as early as 200 BC. Fibonacci numbers appear unexpectedly often in mathematics, so much so that there is an entire journal dedicated to their study, the Fibonacci Quarterly. Applications of Fibonacci numbers include computer algorithms and graphs called Fibonacci cubes.

Fibonacci numbers are strongly related to the golden ratio. They also appear in biological settings, such as branching in trees, the arrangement of leaves on a stem, the fruit sprouts of a pineapple, the flowering of an artichoke, an uncurling fern, and the arrangement of a pine cone's bracts. I wanted to catch the beauty of maths and the beauty of maths in nature with these pictures. I have always loved it when mathematicians write their formula's on blackboards. Have a look, for instance, on the work of Jessica Wynne on this subject.

I have made use of our own chalkboard and my oldest son who is a mathematician for the gum layer behind the palladium layer of the artichoke, cabbage etc. I have been searching for the right color to use to match the look of a chalkboard; so there is only one layer of gum over the palladiumprint.