Look and Say

let lookAndSay = function(nth, number = "1") {
    if (nth === 1) return number;

    let index = 0,
        counter = 1,
        currentNumber = "";

    let result = "";
    while (index < number.length) {
        if (index === 0) {
            currentNumber = number[index];
        }
        else if (currentNumber === number[index]) {
            counter++;
        }
        else if (currentNumber !== number[index]) {
            result = `${result}${counter}${currentNumber}`;//?
            counter = 1;
            currentNumber = number[index];
        }

        index++;
    }

    result = `${result}${counter}${currentNumber}`;//?

    return lookAndSay(--nth, result);
}