Fibonacci Calculator


Type an integer \(n\) in the input to get the \(n\)th Fibonacci number. No recursion or iteration is used.
The classic formula for this is the Binet formula, which gives the \(n\)th Fibonacci number exactly: $$F_n=\frac{1}{\sqrt{5}}\left(\left(\frac{1+\sqrt{5}}{2}\right)^n-\left(\frac{1-\sqrt{5}}{2}\right)^n\right)$$
However, I've used a much simpler formula that requires rounding to the nearest integer: $$F_n=Round\left(\frac{1}{\sqrt{5}}\left(\frac{1+\sqrt{5}}{2}\right)^n\right)$$
\(n\):
\(F_n\): 1