Find out the Sequencing of Fibonacci numbers

fibonacci.js

const fibonacci = (num) => {
  if (Number.isNaN(+num)) {
    return 'not a number';
  }

  let result = 0;
  let tmp = 0;
  let fiArr = [1, 1];

  for (let i = 1; i < num; i++) {
    if (num === 1) {
      result = 0;
      break;
    }
    tmp = fiArr[i] + fiArr[i - 1];
    fiArr.push(tmp);
    if (num === tmp) {
      result = i + 1;
      break;
    }
  }
  console.log(fiArr);
  if (!result) return `${num} in not in fibonacci numbers.`;
  return `the sequence of ${num} fibonacci numbers is ${result}`;
};

console.log(fibonacci(+process.argv[2]));

how to execute it

wget -qO - https://gist.githubusercontent.com/keidarcy/02f4216978a9b049054466428cca9129/raw/51d999239ab80361c300c811a1114896ffddf501/fibonacci.js | node /dev/stdin 55