Arrays 15

using System;
using System.Collections.Generic;
class EratosphenesPrimeNumber
{
    static void Main()
    {
        bool[] numbers = new bool[10000000];
        int j = 2;
        while (j <= Math.Sqrt(numbers.Length))
        {
            if (!numbers[j])
            {
                Console.Write("{0, 2} ", j);
                numbers[j] = true;
                int i = j;
                while (i < numbers.Length)
                {
                    numbers[i] = true;
                    i += j;
                }
            }
            j++;
        }
        for (int i= 2; i < numbers.Length; i++)
        {
            if (!numbers[i]) Console.Write("{0, 2} ", i);
        }
    }
}