using System;

namespace practicals

{

    interface I1

    {

        void Series();

    }

    class Odd:I1

    {

    public void Series()

    {

    int i;

    Console.WriteLine("The odd numbers are");

    for(i=0;i<=20;i++)

    {

    if(i%2!=0)

    {

    Console.WriteLine(i);

    }

    }

    }

    }

    class Program

    {

        public static void Main(string[]arg)

        {

            Odd o1=new Odd();

            I1 obj3;

            obj3=o1;

            obj3.Series();

        }

    }

}

​