[Sieve of Eratosthenes](http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes)

sieve.js

// [Sieve of Eratosthenes](http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes)
var getPrimes = function (max) {
    "use strict";

    var sieve = [],
        primes = [];

    for (var i = 2; i <= max; i += 1) {
        if (!sieve[i]) {
            primes.push(i);

            for (var j = i << 1; j <= max; j += i) {
                sieve[j] = true;
            }
        }
    }

    return primes;
};