Function for divisor of a number

Question

I need a function that gives me the sum of the divisors of a number considering that number and 1 as divisors of that number.

I don't see any wrong in the code

In theory for this concrete example the answer must be 42 for 20 but I get something else.

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are a *really bad* way of posting code or data. Please edit the question with the code, formated with 4 spaces before each code line. — Rui Barradas, Dec 29 '18 at 16:38
Also, see [this](https://math.stackexchange.com/questions/22721/is-there-a-formula-to-calculate-the-sum-of-all-proper-divisors-of-a-number#22723) math.stackexchange question. — Rui Barradas, Dec 29 '18 at 16:55

score 1 · Answer 1 · answered Dec 30 '18 at 11:00

This code should be faster; it also evaluates the divisors and outputs the sum of the divisors in one single function:

sum_divisors <- function(dividend){
   # create a vector from 1 until half of the dividend
   x <- 1:floor(dividend/2)
   # capture the divisors
   divisors_vector <- x[dividend%%x == 0]
   # sum the divisors we found, and the dividend itself
   divisors_sum <- sum(divisors_vector) + dividend
   return(divisors_sum)
}

Function for divisor of a number

1 Answers1