#include <bits/stdc++.h>
using namespace std;

int main() {
    int primes[] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61};
    uint64_t a, b; cin >> a >> b;

    uint64_t ans = 0;
    for (int prime : primes) {
        uint64_t l = (1ULL << (prime - 1));
        uint64_t r = (1ULL << prime) - 1;
        if ((a <= l && l <= b) || (a <= r && r <= b))
            ans += min(b, r) - max(a, l) + 1;
    }

    cout << ans << '\n';
    return 0;
}