#include <iostream>
#include <fstream>
using namespace std;
ifstream input("ucif.in");
ofstream output("ufcif.out");
int main() {
int s = 0, n, prod, i, j;
input >> n;
for (i = 1; i <= n; i++) {
prod = i;
for (j = 1; j < i; j++)
prod = prod * i;
s = s + prod;
}
output << s;
}