#include <iostream>
using namespace std;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int a, b;
	cin >> a >> b;

    static const int primes[] = {
        2, 3, 5, 7, 11, 13, 17, 19,
        23, 29, 31, 37, 41, 43, 47,
        53, 59, 61, 67, 71, 73, 79,
        83, 89, 97
    };
    static const int PRIMES_COUNT = sizeof(primes) / sizeof(primes[0]);

    long sum = 0;
    for (int i = 0; i < PRIMES_COUNT; ++i) {
        int p = primes[i];
        if (p < a || p > b) continue;
        long x = p;
        long fx = x*x*x - x*x + x + 1;
        sum += fx;
    }
    cout << sum << '\n';

	return 0;
}