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# Find Nth term of the series 1, 8, 54, 384…

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

`1, 8, 54, 384...`

Examples:

```Input : 3
Output : 54
For N = 3
Nth term = ( 3*3) * 3!
= 54

Input : 2
Output : 8```

On observing carefully, the Nth term in the above series can be generalized as:

`Nth term = ( N*N ) * ( N! )`

Below is the implementation of the above approach:

## C++

 `// CPP program to find N-th term of the series:``// 1, 8, 54, 384...``#include ``using` `namespace` `std;` `// calculate factorial of N``int` `fact(``int` `N)``{``    ``int` `i, product = 1;``    ``for` `(i = 1; i <= N; i++)``        ``product = product * i;``    ``return` `product;``}` `// calculate Nth term of series``int` `nthTerm(``int` `N)``{``    ``return` `(N * N) * fact(N);``}` `// Driver Function``int` `main()``{``    ``int` `N = 4;` `    ``cout << nthTerm(N);` `    ``return` `0;``}`

## Java

 `// Java program to find N-th term of the series:``// 1, 8, 54, 384...` `import` `java.io.*;` `// Main class for main method``class` `GFG {``    ``public` `static` `int` `fact(``int` `N)``    ``{``        ``int` `i, product = ``1``;``        ``// Calculate factorial of N``        ``for` `(i = ``1``; i <= N; i++)``            ``product = product * i;``        ``return` `product;``    ``}``    ``public` `static` `int` `nthTerm(``int` `N)``    ``{``        ``// By using above formula``        ``return` `(N * N) * fact(N);``    ``}` `    ``public` `static` `void` `main(String[] args)``    ``{``        ``int` `N = ``4``; ``// 4th term is 384` `        ``System.out.println(nthTerm(N));``    ``}``}`

## Python 3

 `# Python 3 program to find``# N-th term of the series:``# 1, 8, 54, 384...` `# calculate factorial of N``def` `fact(N):``    ` `    ``product ``=` `1``    ``for` `i ``in` `range``(``1``, N ``+` `1``):``        ``product ``=` `product ``*` `i``    ``return` `product` `# calculate Nth term of series``def` `nthTerm(N):``    ``return` `(N ``*` `N) ``*` `fact(N)` `# Driver Code``if` `__name__ ``=``=``"__main__"``:``    ``N ``=` `4``    ``print``(nthTerm(N))` `# This code is contributed``# by ChitraNayal`

## C#

 `// C# program to find N-th``// term of the series:``// 1, 8, 54, 384...``using` `System;` `class` `GFG``{``public` `static` `int` `fact(``int` `N)``{``    ``int` `i, product = 1;``    ` `    ``// Calculate factorial of N``    ``for` `(i = 1; i <= N; i++)``        ``product = product * i;``    ``return` `product;``}` `public` `static` `int` `nthTerm(``int` `N)``{``    ``// By using above formula``    ``return` `(N * N) * fact(N);``}` `// Driver Code``public` `static` `void` `Main(String[] args)``{``    ``int` `N = 4; ``// 4th term is 384` `    ``Console.WriteLine(nthTerm(N));``}``}` `// This code is contributed``// by Kirti_Mangal`

## PHP

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## Javascript

 ``

Output:

`384`

Time Complexity: O(N)

Space Complexity: O(1) because using constant variables

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