View Code of Problem 73

#include<iostream>
#include<string>
#include<iomanip>
using namespace std;
int main()
{
	int n,sum=1;
	cin>>n;
	for(int i=1;i<n;i++)
	{
		sum=(sum+1)*2;
		
	}
	cout<<sum<<endl; 
	return 0;
}