# C#: Calculate n terms of square natural number and their sum

## C# Sharp For Loop: Exercise-25 with Solution

Write a C# Sharp program that displays the n terms of square natural numbers and their sum.

The series is as below:

**Sample Solution**:-

**C# Sharp Code:**

```
using System; // Importing necessary namespace
public class Exercise25 // Declaration of the Exercise25 class
{
public static void Main() // Main method, entry point of the program
{
int i, n, sum = 0; // Declaration of variables i, n, and sum as integers
Console.Write("\n\n"); // Displaying new lines
Console.Write("Calculate n terms of square natural number and their sum:\n"); // Displaying the purpose of the program
Console.Write("-----------------------------------------------------------"); // Displaying a separator
Console.Write("\n\n");
Console.Write("Input the number of terms : "); // Prompting the user to input the number of terms
n = Convert.ToInt32(Console.ReadLine()); // Reading the number of terms entered by the user
Console.Write("\nThe square natural upto {0} terms are :", n); // Displaying a message for square natural numbers
// Loop to calculate square natural numbers and their sum
for (i = 1; i <= n; i++)
{
Console.Write("{0} ", i * i); // Displaying the square of natural numbers
sum += i * i; // Calculating the sum of square natural numbers
}
// Displaying the sum of square natural numbers
Console.Write("\nThe Sum of Square Natural Number upto {0} terms = {1} \n", n, sum);
}
}
```

Sample Output:

Calculate n terms of square natural number and their sum: ----------------------------------------------------------- Input the number of terms : 10 The square natural upto 10 terms are :1 4 9 16 25 36 49 64 81 100 The Sum of Square Natural Number upto 10 terms = 385

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**C# Sharp Code Editor:**

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