function smallestCommons(arr) {
	arr.sort((a,b)=>a>b?1:-1)
  let [div, num] = arr

  while(div < arr[1]){
      if(num % div===0) {
				div++;
				} else {
       num += arr[1];
			 div = arr[0]
    }
    }
  return num;
}

console.log(smallestCommons([1,13]));
//console.log(smallestCommons([23,18]));