#include <iostream>
using namespace std;
int main() {
double N, A;
cin >> N >> A;
int P = 1;
int S = A;
for (int i = 0; i < N; i++) {
P += A;
A *= S;
}
cout << P;
return 0;
#include <iostream>
using namespace std;
int main() {
double N, A;
cin >> N >> A;
int P = 1;
int S = A;
for (int i = 0; i < N; i++) {
P += A;
A *= S;
}
cout << P;
return 0;
}