#include <bits/stdc++.h>
#define REP(i,n) for(int i = 0; i < (int)(n); ++i)
typedef long long ll;
using namespace std;

vector<int> prime(int N){
// returns the list of prime numbers below N
    vector<int> v;
    v.push_back(2);
    for(int i=3; i<=N; i+=2){
        bool flag = true;
        for(int j=3; j<=sqrt(i); j+=2){
            if(i%j==0){
                flag = false;
                break;
            }
        }
        if (flag==true) v.push_back(i);
    }
    return v;
}

int main(){
    int N, L;
    cin >> N >> L;
    vector<int> P = prime(L/(N-1));
    ll ans = 0;
    for(int e: P){
        ans += 1+L-e*(N-1);
    }
    ll t = 0;
    cout << max(t,ans) << endl;
    return 0;
}