1.This is the Fibonacci series..
Start with 1 and 1
Add 1 and 1 to get 2
Add 1 and 2 to get 3
Add 2 and 3 to get 5 etc..
2.Fibonacci and the original problem about rabbits where the series first appears, the family trees of cows and bees, the golden ratio and the Fibonacci series, the Fibonacci Spiral and sea shell shapes, branching plants, flower petal and seeds, leaves and petal arrangements, on pineapples and in apples, pine cones and leaf arrangements. All involve the Fibonacci numbers.
It took him an instant, but when Langdon spotted it, he knew it was right.
The Fibonacci sequence