#include <bits/stdc++.h>

const int N = 1e7 + 1;
std::bitset<N> p;

int main() {
    int64_t N, L;
    std::cin >> N >> L;

    int64_t U = (L + 1) / (N - 1);

    for (int i = 3; i * i <= U; i += 2) {
        if (!p[i]) for (int j = i * i; j <= U; j += i) p[j] = true;
    }

    int64_t sum = 2 <= U ? L + 1 - (N - 1) * 2 : 0;
    for (int i = 3; i <= U; i += 2) if (!p[i]) sum += L + 1 - (N - 1) * i;
    
    std::cout << sum << std::endl;
}