Find the Factorial of a Number Using Recursion

The factorial of a number is the product of all the integers from 1 to that number. For example, the factorial of 6 (denoted as 6!) is 1*2*3*4*5*6 = 720. Factorial is not defined for negative numbers and the factorial of zero is one, 0! = 1.

Source Code

# Program to find the
# factorial of a number
# using recursion

recur_factorial <- function(n) {

    if(n == 1) {
        return(n)
    } else { 
        return(n*recur_factorial(n-1))
    }
}

Output

> recur_factorial(5)
[1] 120

Here, we ask the user for a number and use recursive function recur_factorial() to compute the product upto that number.