online resources online resources see the following online resources for information on futureslibrary documentation on futures on futures exercises in mathematicsthe factorial of positive integer ndenoted by !is the product of all positive integers less than or equal to for example note that the value of is write future that will calculate the factorial of any number with the result being printed out via call back function there are several ways in which the factorial value can be calculated either using for loop or recursive function in either case sleep for millisecond between each calculation start multiple futures for different factorial values and see which comes back first