What is a natural number?

Natural numbers are those that allow us to count elements and perform basic calculus operations. They are always positive, non negative integers and are colloquially known as ‘cardinal numbers’. Depending on the definition, they can start either from 0 or 1.

Find the sum of all the multiples of 3 or 5 below 1000.

rm(list = ls())

vec = c(3, 5)

SumOfMultiples <- function(x) {
  iteration = 0
  multiples = c()
  
  for (i in x) {
    while (i*iteration < 1000) {
      multiple = i*iteration
      multiples = c(multiples, multiple)
      iteration = iteration+1
    }
    iteration = 0
  }

  multiples = unique(multiples)
  print(sum(multiples))
}

SumOfMultiples(vec)

## [1] 233168

Find the sum of all the multiples of 3 or 5 below 1000.

rm(list = ls())

multiples = c()

for (i in seq(1, 999)) {
  if (i%%3 == 0 || i%%5 == 0) {
    multiples = c(multiples, i)
  }
}

sum(multiples)

## [1] 233168