using System;

public class Program

{

    public static void Main()

    {

        //Isis Ríos

        int p;

        int n = 2;

        Console.WriteLine("Hi!");

        Console.WriteLine("1, 3, 11, 43, 171...");

        Console.WriteLine("From the past series, what position would you like to know?");

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

        for (int i = 2; i <= p; i++)

        {

            n = 2* n + 1;

        }

         Console.WriteLine(n);

    }

}