sieve of Eratosthenes

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        string now = DateTime.Now.ToString();
        Console.WriteLine("started at: {0}",now);
        List<int> primeNumbers = new List<int>();
        int max = 10000000;

        for (int i = 2; i < max + 1; i++)
        {
            primeNumbers.Add(i);
        }
        double stop = Math.Sqrt((double)max);

        for (int i = 2; i <= stop; i++)
        {
            if (!primeNumbers.Contains(i))
            {
                continue;
            }
            for (int remove = 2*i; remove <= max + 1; remove+=i)
            {
                primeNumbers.Remove(remove);
            }
        }

        foreach (var item in primeNumbers)
        {
            Console.Write(item +" ");
        }
        now = DateTime.Now.ToString();
        Console.WriteLine("ended at: {0}", now);
    }
}