Another special case of iteration is the algebraic product. The Product function is similar to the Summation function, and also requires three arguments. The first argument is evaluated before the multiplication begins, and is generally used to initialize a counter or index variable. The second argument specifies a limit for the counter or index. And the third argument is the quantity to be multiplied in the product. So for example, calling the Product function with the first argument assigning to i, the second argument of and the third argument of i returns the product of all the integers from to This is equivalent to running a For loop that initializes i to runs as long as i is less than or equal to and increases i by one each step. Here, the body inside the for loop would multiply the variable p by the value of i at each step.
