isPrime function

isPrime.js

function isPrime(n) {
  if (n === 1) {
    return false;
  }
  
  if (n === 2) {
    return true;
  }
  
  const root = Math.floor(Math.sqrt(n));
    
  for (let i = 2; i <= root; i++) {   
    if (n % i === 0) {
      return false;
    }
  }
  
  return true;
}

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167].forEach(n => {
  console.log(n + ' is prime: ' + isPrime(n));  
});