R: Fibonacci Numbers

Fibonacci {DescTools} | R Documentation

## Fibonacci Numbers

### Description

Generates Fibonacci numbers.

### Usage

    Fibonacci(n)

### Arguments

`n` | nonnegative integer or vector of nonnegative integers.

### Details

Generates the `n`-th Fibonacci number, whereas Fibonacci(0) = 0.

### Value

A single integer, or a vector of integers.

### Author(s)

Andri Signorell <andri@signorell.net>

### References

http://en.wikipedia.org/wiki/Fibonacci_number

### Examples

    Fibonacci(0)                            # 1
    Fibonacci(2)                            # 2
    Fibonacci(0:3)                          # 0 1 1 2

    # Golden ratio
    F <- Fibonacci(1:25)                    # ... 75025 121393
    f25 <- F[25]/F[24]                      #     1.618033989
    phi <- (sqrt(5) + 1)/2
    abs(f25 - phi)                          # 7.945178e-11

    # Fibonacci numbers without iteration
    fibo <- function(n) {
      phi <- (sqrt(5) + 1)/2
      fib <- (phi^(n+1) - (1-phi)^(n+1)) / (2*phi - 1)
      round(fib)
    }

    fibo(30:33)                             # 1346269 2178309 3524578 5702887

[Package DescTools version 0.99.35 Index]