include <bits/stdc++.h>

using namespace std;

int main() {

int i, j, n, m, sum = 0, ge = 0;
cin >> n >> m;
for (int i = n; i <= m; i++) {
	for (i = n; i < m; i++) {
		sum = 0;
		for (j = 1; j < i; j++) {
			if (i % j == 0)
				sum += j;
		}
		if (sum == j) {
			ge++;
		}
	}
}
cout << ge;
return 0;

}