Let $\left(f_n\right)_{n \in \mathbb{N}}$ be the Fibbonacci sequence. I've seen that: $$ \sum_{n=0}^{+\infty}\frac{1}{f_{2^n}}=\frac{7-\sqrt{5}}{2} $$ I wonder how we can prove this result. Any hint ?
Asked
Active
Viewed 38 times
