using System;

public class Program

{

    public static void Main()

    {

        int n,sum=12,i;

            n=int.Parse(Console.ReadLine());

            if(n%2 != 0)

                Console.WriteLine(n/2*6+1);

                else if(n%2 == 0)

        for(i=0; i<n/2-1 ;i++)

        {   

            sum=sum*2-1 ;

        }

        {

            Console.WriteLine(sum);

        }

​

    }

}