Our Fibonaci Notation

Everyone agrees that Fn+1 = Fn + Fn−1, but how to start? We will use the definition that F0 = 1, F1 = 2. This definition is convenient for us but 1 or 2 off from other definitions. There are Fn bit strings of length n that lack adjacent 1’s.
This site starts off the sequence as u0 = 0 and u1 = 1. But this site starts fibo(0) = fibo(1) = 1. Them too