#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned long long int a, i, r;
  while (scanf("%lld", &a) != EOF) {
    r = 1;
    for (i = 0; i <= a; i++) r = r * 2;
    printf("%lld\n", r - 2);
  }
  return 0;
}
