Smallest Common Multiple (code not efficient enough)

Tell us what’s happening:
Please see smallest common multiple challenge.

My code passes all tests besides the final, which uses large numbers. I am guesing it doesnt pass because it is not efficient enough to process the large numbers.

Any help on how I could change this code to make it more efficient or otherwise finish this challenge would be much appreciated. Thanks.

Your code so far

function smallestCommons(arr) {
  let a = arr.sort((a,b) => a-b) 
  let b = [...Array(a[1]+1).keys()]
  let c = b.slice(b.indexOf(a[0])) 
  // c is array of all numbers to be tested. a and b are just stepping stones to c
  let d = []  
  // empty array that will end up holding every common multiple smaller than fin
  let fin = c.reduce((a,b) => a*b) 
  // all numbers in c multiplied together
    let least = function(nums, f) {
    for (let i of nums) {
      if (nums.every((j) => (f/i)%j == 0)) {
        if (Math.min(...d) != f) {
          let f = Math.min(...d)
          if (nums.every((j) => f%j == 0)){ return least(nums, f) }
    return d[d.length-1] // once a value is reached that is not a common multiple, return the value before
  return least(c, fin) 


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Link to the challenge:

I took this same approach. They use big enough numbers that they kill the ability to use array manipulation.

Check out this approach: