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 = 5Output:45Explanation:For N = 5, Nth term = ( N * ( (N/2) + ( (N%2) * 2) + N ) = ( 5 * ( (5/2) + ( (5%2) * 2) + 5 ) = ( 5 * ( 2 + ( 1 * 2) + 5 ) = 45Input :6Output :54

**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 <iostream> ` `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; ` `} ` |

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## 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)); ` ` ` `} ` `} ` |

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## 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 ` |

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## 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.. ` |

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## PHP

`<?php ` `// PHP program to find N-th term ` `// of the series: 3, 6, 18, 24, 45, 54... ` ` ` `// Function to calculate Nth term of series ` ` ` `function` `nthTerm(` `$N` `) ` `{ ` ` ` `// By using abeove formula ` ` ` `return` `(` `$N` `* ((int)(` `$N` `/ 2) + ` ` ` `((` `$N` `% 2) * 2) + ` `$N` `)); ` `} ` ` ` `// Driver code ` ` ` `// get the value of nthTerm ` `$N` `= 5; ` ` ` `// Calculate and print the Nth term ` `echo` `"Nth term for N = "` `, ` `$N` `, ` ` ` `" : "` `, nthTerm(` `$N` `); ` ` ` `// This code is contributed by ` `// Shashank_Sharma ` `?> ` |

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**Output:**

Nth term for N = 5 : 45

**Time Complexity:** O(1)

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