# Program to find the sum of a Series 1/1! + 2/2! + 3/3! + 4/4! +…….+ n/n!

• Difficulty Level : Hard
• Last Updated : 21 Jul, 2022

You have been given a series 1/1! + 2/2! + 3/3! + 4/4! +…….+ n/n!, find out the sum of the series till nth term.
Examples:

```Input :n = 5
Output : 2.70833

Input :n = 7
Output : 2.71806```

## Java

 `// Java program to print the sum of series` `import` `java.io.*;``import` `java.lang.*;` `class` `GFG {``    ``public` `static` `double` `sumOfSeries(``double` `num)``    ``{``        ``double` `res = ``0``, fact = ``1``;``        ``for` `(``int` `i = ``1``; i <= num; i++) {``            ``/*fact variable store factorial of the i.*/``            ``fact = fact * i;` `            ``res = res + (i / fact);``        ``}``        ``return` `(res);``    ``}` `    ``public` `static` `void` `main(String[] args)``    ``{``        ``double` `n = ``5``;``        ``System.out.println(``"Sum: "` `+ sumOfSeries(n));``    ``}``}` `// Code contributed by Mohit Gupta_OMG <(0_o)>`

## Python3

 `#  program to print the sum of series` `# importing math functions``from` `math ``import``*``n``=``5``s``=``0``# iterating for loop up to n times``for` `i ``in` `range``(``1``,n``+``1``):``  ``# finding the sum series``  ``# factorial function will give you the``  ``# factorial of a number``  ``s``=``s``+``(i``/``factorial(i))``# printing the sum``print``(s)`  `# this code is contributed by gangarajula laxmi`

## C#

 `// C# program to print the sum of series``using` `System;` `class` `GFG {``    ``public` `static` `double` `sumOfSeries(``double` `num)``    ``{``        ``double` `res = 0, fact = 1;``        ``for` `(``int` `i = 1; i <= num; i++)``        ``{``          ` `            ``/*fact variable store factorial of the i.*/``            ``fact = fact * i;` `            ``res = res + (i / fact);``        ``}``        ``return` `(res);``    ``}` `    ``public` `static` `void` `Main(``string``[] args)``    ``{``        ``double` `n = 5;``        ``Console.WriteLine(``"Sum: "` `+ sumOfSeries(n));``    ``}``}` `// This code is contributed by phasing17`

Output

`Sum: 2.708333333333333`

Time Complexity: O(n)

Auxiliary Space: O(1)

Please refer complete article on Program to find the sum of a Series 1/1! + 2/2! + 3/3! + 4/4! +…….+ n/n! for more details!

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