using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading.Tasks;

​

public class Program

{

    public static void Main()

    {

        IEnumerable<int> numbers = Enumerable.Range(3, 1000-3);

       var pQ = 

           from n in numbers.AsParallel()

           where Enumerable.Range(2, (int) Math.Sqrt(n)).All(i => n % i > 0)

           select n;

        int[] primes = pQ.ToArray();

        //foreach(int i in primes)

              // Console.WriteLine(i);

        Parallel.For(0,10000,i => Console.WriteLine(i));

    }

}