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Java program to find sum of factorials from 1 to N

Here, we are implementing a java program that will read the value of N and find sum of the factorials from 1 to N. It is a solution of series 1! + 2! + 3! + 4! + ... N! in java.
Submitted by Chandra Shekhar, on January 06, 2018

Given N and we have find the solution of series 1! + 2! + 3! + 4! + ... N! using Java program. (Sum of the factorials from 1 to N).

Example:

```    Input: 3
Output: 9
Explanation:
1! + 2! + 3! = 1 + 2 + 6 = 9

Input: 5
Output: 152
Explanation:
1! + 2! + 3! + 4! + 5!
= 1+2+6+24+120
= 153
```

Find sum of the factorials using java program

```import java.util.Scanner;

public class SumOfFactorial
{
public static void main(String[] args)
{
// create scanner class object.
Scanner sc = new Scanner(System.in);

// enter the number.
System.out.print("Enter number : ");
int n = sc.nextInt();

int total=0;

int i=1;

// calculate factorial here.
while(i <= n)
{
int factorial=1;
int j=1;

while(j <= i)
{
factorial=factorial*j;
j = j+1;
}
// calculate sum of factorial of the number.
total = total + factorial;
i=i+1;
}
// print the result here.
System.out.println("Sum : " + total);
}
}
```

Output

```First run:
Enter number : 3
Sum : 9

Second run:
Enter number : 5
Sum : 153
```