Program for N-th term of Arithmetic Progression series

Given first term (a), common difference (d) and a integer N of the Arithmetic Progression series, the task is to find N^thterm of the series.
Examples :

Input : a = 2 d = 1 N = 5
Output :
The 5th term of the series is : 6

Input : a = 5 d = 2 N = 10
Output :
The 10th term of the series is : 23

Approach:

We know the Arithmetic Progression series is like = 2, 5, 8, 11, 14 …. … 
In this series 2 is the stating term of the series . 
Common difference = 5 – 2 = 3 (Difference common in the series). 
so we can write the series as :
t₁ = a₁
t₂ = a₁ + (2-1) * d 
t₃ = a₁ + (3-1) * d 
. 
. 
. 
t_N = a₁ + (N-1) * d 

To find the N^th term in the Arithmetic Progression series we use the simple formula .

TN = a1 + (N-1) * d

C++

// CPP Program to find nth term of
// Arithmetic progression
#include <bits/stdc++.h>
using namespace std;

int Nth_of_AP(int a, int d, int N)
{
    // using formula to find the
    // Nth term t(n) = a(1) + (n-1)*d
    return (a + (N - 1) * d);

}

// Driver code
int main()
{
    // starting number
    int a = 2;

    // Common difference
    int d = 1;

    // N th term to be find
    int N = 5;

    // Display the output
    cout << "The "<< N
         <<"th term of the series is : "
         << Nth_of_AP(a,d,N);

    return 0;
}

Java

// Java program to find nth term
// of Arithmetic progression
import java.io.*;
import java.lang.*;

class GFG
{
    public static int Nth_of_AP(int a,
                                int d,
                                int N)
    {
        // using formula to find the Nth
        // term t(n) = a(1) + (n-1)*d
        return ( a + (N - 1) * d );
    }

    // Driver code
    public static void main(String[] args)
    {
        // starting number
        int a = 2;

        // Common difference
        int d = 1;

        // N th term to be find
        int N = 5;

        // Display the output
        System.out.print("The "+ N +
                         "th term of the series is : " +
                          Nth_of_AP(a, d, N));
    }
}

Python3

# Python 3 Program to
# find nth term of
# Arithmetic progression

def Nth_of_AP(a, d, N) :

    # using formula to find the
    # Nth term t(n) = a(1) + (n-1)*d
    return (a + (N - 1) * d)


# Driver code
a = 2  # starting number
d = 1  # Common difference
N = 5  # N th term to be find

# Display the output
print( "The ", N ,"th term of the series is : ",
       Nth_of_AP(a, d, N))



# This code is contributed
# by Nikita Tiwari.

C#

// C# program to find nth term
// of Arithmetic progression
using System;

class GFG
{
    public static int Nth_of_AP(int a,
                                int d,
                                int N)
    {

        // using formula to find the Nth
        // term t(n) = a(1) + (n-1)*d
        return ( a + (N - 1) * d );
    }

    // Driver code
    public static void Main()
    {
        // starting number
        int a = 2;

        // Common difference
        int d = 1;

        // N th term to be find
        int N = 5;

        // Display the output
        Console.WriteLine("The "+ N +
                          "th term of the series is : " +
                           Nth_of_AP(a, d, N));
    }
}

// This code is contributed by vt_m.

PHP

<?php
// PHP Program to find nth term of
// Arithmetic progression

function Nth_of_AP($a, $d, $N)
{
    // using formula to find the
    // Nth term t(n) = a(1) + (n-1)*d
    return ($a + ($N - 1) * $d);

}

// Driver code

// starting number
$a = 2;

// Common difference
$d = 1;

// N th term to be find
$N = 5;

// Display the output
echo("The " . $N . "th term of the series is : " .
                           Nth_of_AP($a, $d, $N));

// This code is contributed by Ajit.
?>

Javascript

<script>

// JavaScript Program to find nth term of
// Arithmetic progression

    function Nth_of_AP(a, d, N)
    {
        // using formula to find the
        // Nth term t(n) = a(1) + (n-1)*d
        return (a + (N - 1) * d);

    }

    // Driver code

    // starting number
    let a = 2;

    // Common difference
    let d = 1;

    // N th term to be find
    let N = 5;

    // Display the output
    document.write("The "+ N + "th term of the series is : "
    + Nth_of_AP(a,d,N));


// This code is contributed by Mayank Tyagi

</script>

Output :

The 5th term of the series is : 6

Time Complexity: O(1), the code will run in a constant time.
Auxiliary Space: O(1), no extra space is required, so it is a constant.