#include <iostream>
#include <vector>
using namespace std;

int PrimeNumber(long long n, long long m) {
    vector<int> Prime;
    int p, i = 1;
    long long sum = 0, count = 1;
    Prime.insert(Prime.end(), 2);
    while (count < m) {
        for (int j = 0; j < Prime.size();  j++) {
            if (i % Prime[j] == 0) {p += 1; break;}
        }
        if (p == 0) {count += 1; Prime.insert(Prime.end(), i); if (count >= n) {sum += i;};}
        else p = 0;
        i += 2;
    }
    if (n == 1) sum += 2;
    return sum;
}

int main() {
    long long n, m;
    cin >> n >> m;
    cout << PrimeNumber(n, m);
}