The Fibonacci Sequence.
The Fibonacci Sequence is a number pattern where you take the last two numbers and add them together. We start off with number 1, and then another 1. 1+1=2. As you can now see, the last two numbers are 1 and 2. Lets carry on. 1+2=3+2=5=3=8. The fibonacci sequence goes like 1,1,2,3,5,8,13,21,34,55,89 and so on.