Program to find the Nth term of series 5, 10, 17, 26, 37, 50, 65, 82, …

Given a number N. The task is to write a program to find the Nth term of the below series:

5, 10, 17, 26, 37, 50, 65, 82, …(N Terms)

Examples:

Input: N = 4
Output: 82
For N = 4
4th Term = ( 4 * 4 + 2 * 4 + 2) 
         = 26
Input: N = 10
Output: 122

Approach: The generalized Nth term of this series: 

Below is the required implementation: 

C++

// CPP program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
#include <iostream>
#include <math.h>
using namespace std;

// calculate Nth term of series
int nthTerm(int n)
{
    return pow(n, 2) + 2 * n + 2;
}

// Driver Function
int main()
{
    int N = 4;

    cout << nthTerm(N);

    return 0;
}

Java

// Java program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
import java.util.*;

class solution
{

// calculate Nth term of series
static int nthTerm(int n)
{

    //return the final sum
    return (int)Math.pow(n, 2) + 2 * n + 2;
}

// Driver Function
public static void main(String arr[])
{
    int N = 4;

    System.out.println(nthTerm(N));

}

}
//This code is contributed by Surendra_Gangwar

Python3

# Python3 program to find the N-th
# term of the series:
# 5, 10, 17, 26, 37, 50, 65, 82, ...

# from math lib. import everything
from math import *

# calculate Nth term of series
def nthTerm(n) :

    return pow(n, 2) + 2 * n + 2

# Driver code
if __name__ == "__main__" :

    N = 4
    print(nthTerm(N))

# This code is contributed by
# ANKITRAI1

C#

// C# program to find the
// N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
using System;

class GFG
{

// calculate Nth term of series
static int nthTerm(int n)
{

    //return the final sum
    return (int)Math.Pow(n, 2) +
                    2 * n + 2;
}

// Driver Code
public static void Main()
{
    int N = 4;

    Console.Write(nthTerm(N));
}
}

// This code is contributed
// by ChitraNayal

PHP

<?php
// PHP program to find the
// N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...

// calculate Nth term of series
function nthTerm($n)
{
    return pow($n, 2) + 2 * $n + 2;
}

// Driver Code
$N = 4;
echo nthTerm($N);

// This code is contributed
// by Akanksha Rai(Abby_akku)

Javascript

<script>
// JavaScript program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...


// calculate Nth term of series
function nthTerm( n)
{
    return Math.pow(n, 2) + 2 * n + 2;
}

// Driver code

    let N = 4;
   document.write( nthTerm(N) );

// This code contributed by aashish1995

</script>

Output:

26

Time Complexity: O(1)

Space Complexity: O(1) since using constant variables