Fibonacci numbers
From specialfunctionswiki
The Fibonacci sequence is defined by $$F_{n+2}=F_n+F_{n+1},F_1=F_2=1.$$
Videos
The Golden Ratio & Fibonacci Numbers: Fact versus Fiction
Doodling in Math: Spirals, Fibonacci, and Being a Plant (1 of 3)
Fibonacci mystery
See also
Reciprocal Fibonacci constant
Lucas numbers
