# Program to find Nth term of the series 3, 6, 18, 24, …

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

```3, 6, 18, 24, 45, 54...(Nth term)
```

Examples:

```Input: N = 5
Output: 45
Explanation:
For N = 5,
Nth term = ( N * ( (N/2) + ( (N%2) * 2) + N )
= ( 5 * ( (5/2) + ( (5%2) * 2) + 5 )
= ( 5 * ( 2 + ( 1 * 2) + 5 )
= 45

Input : 6
Output : 54
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Generalized Nth term of this series:

`Nth term = ( N * ( (N/2) + ((N%2) * 2) + N )`

Below is the implementation of the above approach:

## C++

 `// CPP program to find N-th term of the series: ` `// 3, 6, 18, 24, 45, 54... ` ` `  `#include ` `using` `namespace` `std; ` ` `  `// function to calculate Nth term of series ` `int` `nthTerm(``int` `N) ` `{ ` `    ``// By using above formula ` `    ``return` `(N * ((N / 2) + ((N % 2) * 2) + N)); ` `} ` ` `  `// Driver Function ` `int` `main() ` `{ ` ` `  `    ``// get the value of N ` `    ``int` `N = 5; ` ` `  `    ``// Calculate and print the Nth term ` `    ``cout << ``"Nth term for N = "` `         ``<< N << ``" : "` `         ``<< nthTerm(N); ` ` `  `    ``return` `0; ` `} `

## Java

 `import` `java.io.*; ` ` `  `// Class to calculate Nth term of series ` `class` `Nth { ` `    ``public` `int` `nthTerm(``int` `N) ` `    ``{ ` `        ``// By using above formula ` `        ``return` `(N * ((N / ``2``) + ((N % ``2``) * ``2``) + N)); ` `    ``} ` `} ` ` `  `// Main class for main method ` `class` `GFG { ` ` `  `    ``public` `static` `void` `main(String[] args) ` `    ``{ ` ` `  `        ``// get the value of N ` `        ``int` `N = ``5``; ` ` `  `        ``// create object of Class Nth ` `        ``Nth a = ``new` `Nth(); ` ` `  `        ``// Calculate and print the Nth term ` `        ``System.out.println(``"Nth term for N = "` `                           ``+ N + ``" : "` `                           ``+ a.nthTerm(N)); ` `    ``} ` `} `

## Python3

 `# Python3 program to find N-th term of the series:  ` `# 3, 6, 18, 24, 45, 54...  ` ` `  ` `  `# function to calculate Nth term of series  ` `def` `nthTerm( N):  ` `    ``# By using above formula  ` `    ``return` `(N ``*` `((N ``/``/` `2``) ``+` `((N ``%` `2``) ``*` `2``) ``+` `N))  ` ` `  ` `  `# Driver Function  ` ` `  `# get the value of N  ` `if` `__name__``=``=``'__main__'``: ` `    ``N ``=` `5` ` `  `    ``# Calculate and print the Nth term  ` `    ``print``( ``"Nth term for N = "``, N ,``" : "``, nthTerm(N))  ` ` `  ` `  `# This code is contributed by ash264 `

## C#

 `// C# program to find N-th  ` `// term of the series: ` `// 3, 6, 18, 24, 45, 54... ` `using` `System; ` ` `  `class` `GFG ` `{ ` `public` `int` `nthTerm(``int` `N) ` `{ ` `    ``// By using above formula ` `    ``return` `(N * ((N / 2) + ` `           ``((N % 2) * 2) + N)); ` `} ` ` `  `// Driver Code ` `public` `static` `void` `Main() ` `{ ` ` `  `    ``// get the value of N ` `    ``int` `N = 5; ` ` `  `    ``// create object of Class Nth ` `    ``GFG a = ``new` `GFG(); ` ` `  `    ``// Calculate and print the Nth term ` `    ``Console.WriteLine(``"Nth term for N = "` `+  ` `                                ``N + ``" : "` `+  ` `                             ``a.nthTerm(N)); ` `} ` `} ` ` `  `// This code is contributed  ` `// by inder_verma.. `

## PHP

 ` `

Output:

```Nth term for N = 5 : 45
```

Time Complexity: O(1)

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