Given an=an−1+an−2a_n = a_{n-1} + a_{n-2}an=an−1+an−2, which identity relates the sequence to the golden ratio ϕ\phiϕ?
limn→∞an+1an=ϕ\lim_{n \to \infty} \frac{a_{n+1}}{a_n} = \philimn→∞anan+1=ϕ
an=ϕn+ψna_n = \phi^n + \psi^nan=ϕn+ψn
an2−an−1an+1=(−1)na_n^2 - a_{n-1}a_{n+1} = (-1)^nan2−an−1an+1=(−1)n
an=ϕan−1a_n = \phi a_{n-1}an=ϕan−1