#include <iostream>
using namespace std;

bool prime[int(1e7) + 1];

void makeprime(){for(int i = 2;i * i <= 1e7 + 1;i++) if(!prime[i]) for(int j = 2 * i;j < int(1e7) + 1;j += i) prime[j] = true;}

int main(){
	makeprime();
	long long ans = 0,n,l;
	cin >> n >> l;
	for(int i = 2;i < int(1e7) + 1;i++) if(!prime[i]) ans += max(0ll,l - (n - 1) * i + 1);
	cout << ans << endl;
}