code: function isPrime (n) {
    if (n === 1) return false
    if (n === 2) return true
  
    var m = Math.sqrt(n)
  
    for (var i = 2; i <= m; i++) if (n % i === 0) return false
  
    return true
  }
docs: Check if a number is prime
  
  @param {Number} n
  
  @returns {Boolean}