JAVASCRIPT

factorial of number js

const factorialize = num => {
  if (num === 0 || num === 1) {
    return 1;
  }
  for (let i = num - 1; i >= 1; i--) {
    num *= i;
  }
  return num;
};

math.factorial

math.factorial(5)

factorial js

function factorial(n) {
  return (n + 1) * (n / 2);
}