var primeNumbers = [];
var numbers = [];
var j = 2;
var n = 100;

for (var i = 2; i < n; i++) {
  numbers[i]= i;
}

function sieve (p) {

  do {

    for (i = j * 2; i < p; i += j) {
      numbers[i] = false;
    }

    for (i = j + 1; i < p; i++) {
      if (numbers[i]) break;
    }

    j = i;

  } while (j * j < p);


  for (i = 0; i < n; i++) {
    if (numbers[i]) {
      primeNumbers.push(numbers[i]);
    }
  }
}

sieve(n);

console.log(primeNumbers);