#include <iostream>
using namespace std;

int main(void){
//input
	int p; cin >> p;
//calc
	int prime=1;
	for(int i=0;i<p;i++){
		prime *= 2;
	}
	prime -= 1;
	
	int cnt=0;
	while(prime > 0){
		if(prime % 2 == 1){
			cnt++;
		}
		prime /= 2;
	}
//output
	cout << cnt << endl;
}