Program toward print sum regarding factorial regarding Odd series in C#

C# Program toward print sum regarding factorial regarding Odd series

Program Statement:

Write a program toward display the sum regarding the following series i.e. sum regarding the factorial regarding odd series

1! + 3! + 5! + 7! + 9! + . . . + n!

Solution:

 static void Main(string[] args)
        {
            int i, j, f,last, sum = 0;
            Console.WriteLine("Enter Last value:");
            last = Convert.ToInt32(Console.ReadLine());
            i = 1;
            while (i <= last)
            {
                f = 1;
                j = i;
                while (j >= 1)
                {
                    f = f * j;
                    j--;
                }
                sum = sum + f;
                Console.WriteLine("factorial regarding " +i+"="+f);
                i = i + 2;
            }
            Console.WriteLine("sum regarding all factorial = " + sum);
            Console.ReadLine();
        }