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# Find Nth term of the series 5, 13, 25, 41, 61…

• Difficulty Level : Easy
• Last Updated : 15 Mar, 2021

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

`5, 13, 25, 41, 61...`

Examples:

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```Input : 3
Output : 25
For N = 3
Nth term = 3*3 + (3+1)*(3+1)
= 25
Input : 5
Output : 61```

On observing carefully, the Nth term of the given series can be generalised as:

`Nth term = N2 + (N+1)2`

Below is the implementation of the above approach:

## C++

 `// CPP program to find N-th term of the series:``// 5, 13, 25, 41, 61...``#include ``using` `namespace` `std;` `// calculate Nth term of series``int` `nthTerm(``int` `N)``{``    ``return` `N * N + (N + 1) * (N + 1);``}` `// Driver Function``int` `main()``{``    ``int` `N = 3;` `    ``cout << nthTerm(N);` `    ``return` `0;``}`

## Java

 `// Java program to calculate Nth term of``// the series: 5, 13, 25, 41, 61...` `import` `java.io.*;` `class` `Nth {``    ``public` `static` `int` `nthTerm(``int` `N)``    ``{``        ``// By using above formula``        ``return` `N * N + (N + ``1``) * (N + ``1``);``    ``}``    ` `    ``public` `static` `void` `main(String[] args)``    ``{``        ``int` `N = ``3``; ``// Nth term is 25``        ` `        ``// call and print Nth term``        ``System.out.println(nthTerm(N));``    ``}   ``}`

## Python 3

 `# Python 3 program to find``# N-th term of the series:``# 5, 13, 25, 41, 61...` `# Function to calculate``# Nth term of series``def` `nthTerm(N) :``    ``return` `N ``*` `N ``+` `(N ``+` `1``) ``*` `(N ``+` `1``)` `# Driver Code``if` `__name__ ``=``=` `"__main__"` `:` `    ``N ``=` `3` `    ``# function calling``    ``print``(nthTerm(N))` `# This code is contributed``# by ANKITRAI1`

## C#

 `// C# program to calculate Nth term of``// the series: 5, 13, 25, 41, 61...``using` `System;` `class` `GFG``{``public` `static` `int` `nthTerm(``int` `N)``{``    ``// By using above formula``    ``return` `N * N + (N + 1) * (N + 1);``}` `// Driver Code``public` `static` `void` `Main()``{``    ``int` `N = 3; ``// Nth term is 25``    ` `    ``// call and print Nth term``    ``Console.Write(nthTerm(N));``}``}` `// This code is contributed``// by ChitraNayal`

## PHP

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## Javascript

 ``
Output:
`25`

Time Complexity: O(1)

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