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

int N, L;
bool is_prime[5000001];
vector<int> primes;
int pmax;

signed main()
{
	cin >> N >> L;

	//考えるべき素数の上限
	pmax = L / (N - 1) + 10;
	pmax = 5000001;
	
	rep(i,pmax) is_prime[i] = true;

	for (int i=2; i<=pmax; i++)
	{
		if (is_prime[i])
		{
			primes.push_back(i);
			for (int j=i; j<=pmax; j+=i)
			{
				is_prime[j] = false;
			}
		}
	}

	int ans = 0;

	rep(i,primes.size())
	{
		if (primes[i] * (N - 1) <= L)
		{
			ans += L - primes[i] * (N - 1) + 1;
		}
		else
		{
			break;
		}
	}

	cout << ans << endl;
}