#include <bits/stdc++.h> using namespace std; typedef long long int ll; typedef pair<ll,ll> P; typedef vector<ll> VI; typedef vector<VI> VVI; #define REP(i,n) for(int i=0;i<(n);i++) #define ALL(v) v.begin(),v.end() template<typename T> bool chmax(T &x, const T &y) {return (x<y)?(x=y,true):false;}; template<typename T> bool chmin(T &x, const T &y) {return (x>y)?(x=y,true):false;}; constexpr ll MOD=998244353; constexpr ll INF=2e18; int main() { ll l, r; cin >> l >> r; VI f(r-l+1,0); ll rt; for(ll i=1;i<=1000000;i++){ ll s=(l/i)*i; if(s<l) s+=i; for(ll j=s;j<=r;j+=i){ rt=sqrt(j/i); if(rt!=1&&rt*rt==j/i) f[j-l]=1; } if(i==1) continue; ll k=i*i; s=(l/k)*k; if(s<l) s+=k; for(ll j=s;j<=r;j+=k){ f[j-l]=1; } } int ans=0; for(ll i=l;i<=r;i++) ans+=!f[i-l]; cout << ans << endl; return 0; }