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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

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