To find out prime no of particular range in c#.net

It is simple program in c#.net to find the prime no of particular range

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace prime
{
class Program
{
static void Main(string[] args)
{
Int32 i, j;
Int32 n = 20;
for(i=1;i
{
for (j = 2; j <= i; j++)
{
if (i % j == 0)
{
break;
}
}
if (j == i)
{
Console.Write(j);
Console.WriteLine();
}
}
Console.ReadKey();
}
}
}