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

const int N = 1e5 + 10;

int primes[N], cnt; // primes[]存储所有素数
bool st[N];         // st[x]存储x是否被筛掉

int factor[N]; // 存储每一个数的质因子个数

void get_primes(int n) {
    memset(st, 0, sizeof st);
    for (int i = 2; i <= n; i++) {
        if (!st[i]) {
            primes[cnt++] = i;
            factor[i] = 1; // 质数的质因子个数是1
        }
        for (int j = 0; primes[j] * i <= n; j++) {
            st[primes[j] * i] = true;              // 标识primes[j] * i是个合数
            factor[primes[j] * i] = factor[i] + 1; // t=primes[j]*i,那么t的质因子个数=i的质因子个数+1
            if (i % primes[j] == 0) break;         // 只被最小的质数因子筛掉
        }
    }
}

int main() {
    int n, m;
    cin >> n >> m;

    get_primes(m);

    int res = 0;
    for (int i = n; i <= m; i++) {
        res = max(res, factor[i]);
        // printf("The count of prime factor(s) of %d is: %d\n", i, factor[i]);
    }
    cout << res << endl;
    return 0;
}