#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <cmath>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <stdlib.h>
#include <stdio.h>
#include <bitset>
using namespace std;
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
typedef long long ll;

const ll MAX = 10000000;
bool isPrime[MAX];
vector<ll> prime;
void makePrime(){
  for (ll i = 0; i < MAX; i++){
    isPrime[i] = true;
  }
  for (ll i = 2; i < MAX; i++){
    if(isPrime[i]){
      prime.push_back(i);
      for (ll j = 2 * i; j < MAX; j += i) {
        isPrime[j] = false;
      }
    }
  }
  return;
}
int main(){
  ll N, L;
  cin >> N >> L;
  // L / (N - 1) 以下の素数の個数
  makePrime();
  ll ans = 0;
  FOR(i, 0, prime.size()){
    if(prime[i] * (N - 1) <= L) ans += (L - (prime[i] * (N - 1))) + 1;
    else break;
  }
  cout << ans << endl;
  return 0;
}