Number Generator With JS

<h1>Gerador de nmeros</h1><form name="form_main">  <div>    <label for="number">Quantidade</label>    <input type="number" id="number" />  </div>  <div>    <label for="type">Tipo</label>    <input type="radio" name="type" id="odd" value="odd" />    <label for="odd">Impar</label>    <input type="radio" name="type" id="even" value="even" />    <label for="even">Par</label>    <input type="radio" name="type" id="real" value="real" checked='checked' />    <label for="real">Reais</label>  </div>  <button type="button" name="generate">Gerar</button>  <div id="output"></div></form>

"use strict";let button = document.form_main.generate;button.addEventListener('click', generate);function generate() {  let output = document.getElementById('output');  let total = document.form_main.number.value;  let type = document.form_main.type.value;  let numbers = [];  switch (type) {    case 'odd':      numbers = generateOdd(total);      break;    case 'even':      numbers = generateEven(total);      break;    case 'real':    default:      numbers = generateReal(total);      break;  }  output.innerHTML = numbers;}function generateOdd(total) {  let numbers = [];  let odd = 0;  for (let index = 0; index < total; index++) {    while (odd % 2 == 0) { odd++; }    numbers.push(odd);    odd++;  }  return numbers;}function generateEven(total) {  let numbers = [];  let even = 0;  for (let index = 0; index < total; index++) {    while (even % 2 != 0) { even++; }    numbers.push(even);    even++;  }  return numbers;}function generateReal(total) {  let numbers = [];  for (let index = 0; index < total; index++) {    numbers.push(index);  }  return numbers;}