Next I write a program to display the permutations for n numbers with JavaScript. First, we need to understand that from these n numbers, we can first take any one number from it, and the (n-1) numbers remaining has the similar property as the n numbers, we need to find the permutations for the (n-1) numbers, and from these (n-1) numbers, we take any one of them and there are (n-2) numbers which we need to find the permutations of them. So the whole process will stop when there is only one number left, we will can display the permutations. It is a recursive process.