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- Recursion: Fibonacci Numbers

# Recursion: Fibonacci Numbers

# Recursion: Fibonacci Numbers

*The Fibonacci Sequence*

The Fibonacci sequence appears in nature all around us, in the arrangement of seeds in a sunflower and the spiral of a nautilus for example.

The Fibonacci sequence begins with and as its first and second terms. After these first two elements, each subsequent element is equal to the sum of the previous two elements.

Programmatically:

Given , return the number in the sequence.

**Example**

The Fibonacci sequence to is . With zero-based indexing, .

**Function Description**

Complete the recursive function in the editor below.

fibonacci has the following parameter(s):

*int n:*the index of the sequence to return

**Returns**

- *int:* the element in the Fibonacci sequence

**Input Format**

The integer .

**Constraints**

**Sample Input**

STDIN Function ----- -------- 3 n = 3

**Sample Output**

```
2
```

**Explanation**

The Fibonacci sequence begins as follows:

...

In the sequence above, is .