#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#define _GLIBCXX_DEBUG
using namespace std;
using std::cout;
using std::cin;
using std::endl;
using ll=long long;
using ld=long double;
ll ILL=1167167167167167167;
const int INF=2100000000;
ll mod=998244353;
#define rep(i,a) for (ll i=0;i<a;i++)
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> ll LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> ll UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,const T &b){if(a>b){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,const T &b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
void yneos(bool a){if(a) cout<<"Yes\n"; else cout<<"No\n";}

vector<int> Mobius(int N){
	vector<int> ans(N+1,-1);
	vector<bool> p(N+1,true);
	ans[0]=0,ans[1]=1;
	for(int i=2;i*i<=N;i++){
		if(p[i]){
			for(int j=i*2;j<=N;j+=i){
				if(p[j]){
					p[j]=false;
				}
				else ans[j]*=-1;
			}
			for(int j=i*i;j<=N;j+=i*i){
				ans[j]=0;
			}
		}
	}
	return ans;
}

//おちこんだりもしたけれど、私はげんきです。
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	
	ll L,R;
	cin>>L>>R;
	ll ans=R-L+1;
	ll M=1e6;
	auto mo=Mobius(M);
	/*rep(i,11) cout<<mo[i]<<" ";
	cout<<endl;*/
	for(ll i=2;i<=M;i++){
		ll x=i*i;
		ans+=mo[i]*(R/x-(L-1)/x);
	}
	if(L>M*M){
		ll l=M,r=1e9+1;
		while(r-l>1){
			ll D=(l+r)/2;
			if(L>D*D) l=D;
			else r=D;
		}
		if(r*r<=R){
			ans--;
			rep(i,M){
				if(i<2) continue;
				if(r%i==0){
					ans++;
					break;
				}
			}
		}
	}
	cout<<ans<<"\n";
}