Practicum4-VII-16

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

namespace ConsoleApp1
{
    class Program
    {
        static void Main()
        {
            Console.WriteLine("Please, enter the a = ");
            int a = int.Parse(Console.ReadLine());
            Console.WriteLine("Please, enter the b = ");
            int b = int.Parse(Console.ReadLine());
            while (a < b)
            {
                int c = 2*a + 1;
                int k = c;
                for (int i = a + 1; i > 1; i--)
                {
                    if (c % i == 0)
                    {
                        c = c / i; break;
                    }

                }
                if (c != k)
                {
                    Console.WriteLine("{0},{1};", a, (a + 1));
                }
                a++;
            }
        }
    }
}