# Python Program to find the Sum of Arithmetic Progression

In this tutorial, we will discuss a Python program to find the sum of an arithmetic progression (AP).

Before going to the program first, let us understand what is an *Arithmetic Progression(AP).*

**Arithmetic Progression (AP):**

- An arithmetic progression is a sequence of numbers in which the difference between consecutive terms is constant.
- The sum of the first $n$ terms of an AP is given by the formula: $S_{n}=2n (2a+(n−1)d)$, where $a$ is the first term and $d$ is a common difference.

**Related: ** Python Program to find the Sum of Geometric Progression

#### Program code for Arithmetic Progression in Python

# Sum of an Arithmetic Progression in Python def sum_of_ap(a, d, n): return (n / 2) * (2 * a + (n - 1) * d) a = float(input("Enter the first term (a): ")) d = float(input("Enter the common difference (d): ")) n = int(input("Enter the number of terms (n): ")) sum_ap = sum_of_ap(a, d, n) print(f"The sum of the first {n} terms of the AP is {sum_ap}.")

#### Explanation

**Function Definition**: The`sum_of_ap`

function takes three parameters:`a`

,`d`

, and`n`

, and returns the sum of the first $n$ terms of the AP.**Main Program**: The program prompts the user to enter the first term, common difference, and number of terms. It then calculates the sum of the AP using the`sum_of_ap`

function and prints the result.

#### Output

- When you run the above program, it will prompt you to enter the first term, common difference, and number of terms.
- After entering the values, it will calculate the sum of the AP and print the result.

#### Conclusion

- In this tutorial, we learned how to find the sum of an arithmetic progression (AP) using a Python program.
- Understanding this concept is essential for solving various mathematical problems and enhancing your programming skills.