I need help writing a simple and easy to understand program

I need help writing a simple and easy to understand program using Java. Here is the exercise I need help with:

You can approximate pi by using the following series:

pi = 4(1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 + . . . + (-1)ⁱ⁺¹/ 2i - 1)

Write a program that displays the pi value for i = 10000, 20000, . . ., and 100000.

Solution

public class piValue {

   /**
   * @param args
   */
   public static void main(String[] args) {
       // TODO Auto-generated method stub
       double pi=0;
       int i;
       for(i=1;i<=10000;i++)
       {
           pi += Math.pow(-1, i) * (double)1/(2*i-1);
       }
       pi*=4;
       System.out.println(\"Value of Pi with i =\"+(i-1)+\" is =\"+pi);

   }

}

o/p

Value of Pi with i =10000 is =-3.1414926535900345

Put the value of i at which you want to calculate Pi