**Fibonacci numbers**form a sequence defined by the following formula:

That is, after two starting values,each number is the sum of the two preceding numbers. The first Fibonacci numbers also denoted as

*Fn*, for

*n*= 0, 1, … , are:

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025…

Sometimes this sequence is considered to start at

*F*1 = 1, but it is more common to include

*F*0 = 0.

The Fibonacci numbers are named after Leonardo of Pisa, known as Fibonacci.