# Recursion in Flowgorithm Flowchart

### Overview

In this tutorial, we will understand Recursion using Flowgorithm flowchart. In the earlier example using Function, we have noticed that the Main flowchart calls the function. However, a recursive function is a function that calls itself. A function that calls itself is a recursive function.

Mathematical notation for the sum is

Alternatively, we can define the sum series as:

### Recursive calls

Let’s design a recursive function to compute the sum of N positive numbers called **RSum**. Sum of n numbers in recursive format:

Base case: When n= 1 the sum is 1. This is the halting case. We should tell the function to stop the recursive calls.

**Recursive case:**

**RSum = n + RSum(n-1)**

This in turn changes to in the next recursion:

**RSum = n + (n-1) + RSum(n-2)**

and so on until we reach the base case.

### Example Flowchart

**RSum** is the recursive function. The **Main** function prompts the user for the number N. The **Main** function invokes the recursive function with the parameter N.

The recursive function **RSum** calls itself to compute the sum of N natural numbers.

### Sample Output

Execute the Main flowchart and verify the output.

If the flowchart is N the flowchart output of the recursive function should be:

N*(N+1)/2

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**Flowgorithm Tutorials Link:**

https://www.testingdocs.com/flowgorithm-flowchart-tutorial/

**Flowgorithm Website:**