using System;

public class Program

{

    public static void Main()

    { 

        Console.Clear();

        start:

        Console.WriteLine("Type initial value");

        int n1 = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("Type limit");

        int n2 = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("Type increment");

        int inc = Convert.ToInt32(Console.ReadLine());

        if (n1 < n2 && inc > 0 && inc < (n2-n1))

        {

            for(int i = n1; i <= n2; i+= inc)

            {

                Console.Write("{0} ", i); 

            }

        }

        else {

            Console.WriteLine("Please type the values again");

            goto start;

        }

    }

}

​