#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, e) for (int i = (int)(s); i < (int)(e); ++i)

int main() {
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	
	int N, L;
	cin >> N >> L;
	
	int maxi = 10000100;
	vector<bool> isPrime(maxi, true);
	isPrime[0] = isPrime[1] = false;
	rep(p, 2, maxi) if (isPrime[p]) {
		for (int q = p*2; q < maxi; q += p) isPrime[q] = false;
	}
	
	ll ans = 0;
	rep(p, 2, maxi) if (isPrime[p]) {
		if (L < p*(N - 1)) break;
		ans += L - p*(N - 1) + 1;
	}
	cout << ans << '\n';
}