#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cassert>
#include <iostream>
#include <iomanip>
#include <string>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <bitset>

#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()
#define debug(x) cerr << #x << ": " << x << endl

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef pair<int, int> Pii;

const ll MOD = 1000000007;
const long double EPS = 1e-10;
const int dyx[4][2] = {
    { 0, 1}, {-1, 0}, {0,-1}, {1, 0}
};

vector<int> primes;
int is_not_prime[1000001], connected[1000001];

int main() {
    std::ios::sync_with_stdio(0); cin.tie(0);
    int n, p;
    cin >> n >> p;

    if(p == 1) {
        cout << "1\n";
        return 0;
    }

    is_not_prime[1] = 1;
    for(int i=2;i<=n;++i) {
        if(is_not_prime[i]) continue;
        primes.push_back(i);
        int j = i+i;
        while(j <= n) {
            is_not_prime[j] = 1;
            j += i;
        }
    }

    int min_i = (is_not_prime[p]?0:distance(primes.begin(), (lower_bound(primes.begin(), primes.end(), p))));
    int max_i = (is_not_prime[p]?distance(primes.begin(), (--upper_bound(primes.begin(), primes.end(), n/primes[min_i]))):min_i);
    // cerr << primes[min_i] << " " << primes[max_i] << endl;

    for(int i=min_i;i<=max_i;++i) {
        for(int j=primes[i];j<=n;j+=primes[i]) {
            connected[j] = 1;
        }
    }

    int ans = 0;
    for(int i=1;i<=n;++i) {
        if(connected[i]) ++ans;
    }
    cout << ans << endl;
    return 0;
}