View Code of Problem 73

#include<stdio.h>
#include<cstdlib>
#include<cmath>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long ll;
int main(){
	int n;
	scanf("%d", &n);
	int sum=1;
	for(int i=1;i<n;i++){
		sum=(sum+1)*2;
	}
	printf("%d\n", sum);
	return 0;
}