Fibonacci is really a johnny-come-lately when it comes to number sequences and the golden section, in particular ..... in fact, Pythagoras knew about such numbers, around 600 BC.
There's more than one such sequence of numbers, but the golden section (1.618/.618) is the best known to modern generations.
It is reflected in nature right around the globe, but the first instance was probably at the time our solar system was created.
Specifically, the direct relationship between the Earth and the movement of Venus, our closest neighbour towards the Sun.
Here's the proof :
Earth moves 360 degrees in one year
Venus moves approximately 583 degrees in one year
Venus/Earth = 583/360 = 1.619
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Gann found for trading purposes, the numbers 55, 144 and 233 in the Fibo sequence, to be the most important.
In fact, in 360 degrees, there's 19 numbers that made up Gann's trading cycles, which he took directly from the bible .....
Believe it or not. :)
All of the above can be proven, beyond doubt, using tetragrams, simple mathematics and some geometry.