#include<bits/stdc++.h>
using namespace std;
#define nl "\n"
#define fi first
#define se second
#define pb push_back
#define ll long long
#define ull unsigned ll
#define RV  return void
#define sz(x) int(x.size())
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define fixed(n) fixed << setprecision(n)
#define cin(v) for (auto&i:v) cin >> i;
#define cout(v) for (auto&i:v) cout << i << " ";
#define clr(memo, x) memset(memo, x, sizeof memo)
#define FastCode ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

void  Zainab(){
            // #ifndef ONLINE_JUDGE
              freopen("longpath.in", "r", stdin);
              freopen("longpath.out", "w", stdout);
            // #endif
}

const ll N = 1e7;
vector < bool > isPrime (N + 1 , true);
vector < ll > primes ;

void pre(){
    isPrime[0]= isPrime[1]=false;

    for(ll i = 2 ; i * i <= N ; i++)
        if(isPrime[i])
            for(ll j = i * i ; j <= N ; j +=i )
                isPrime[j] = false;

    for(ll i =0 ; i < N+1 ; ++i )
        if(isPrime[i]) primes.pb(i);

}

void myCode(){


ll n;
cin >> n ;

// ll sum =0;
// __int128 fact =1;
// for(ll i =1 ; i <= 100 ; i++) {
//     // long double temp = cos(  (fact + 1 )/i  *3.1415926 );
//     // cout << i << " " << temp * temp << nl;
//     if( (fact + 1 ) % i==0){
//          sum ++;
//         cout << i << " " << sum << nl;
//     }
//     fact *=i;
// }

// cout << sum << nl << nl;


long double mo = 1 , lg = ceil(log2(n));
ll l =0 ,r = sz(primes) -1 ;
while(l <= r ){
    ll mid = r - (r-l)/2;
    if(primes[mid] <= n) {
        l = mid+1;
        mo = mid + 2;
    }
    else
        r = mid-1;
}

// cout << mo << "  ";

cout << fixed(6) << pow( lg / mo , 1/lg) << nl;

}


int main(){
                                   FastCode ;
                                    //  Zainab() ;

    int testCase=1;
         cin >> testCase ;
    pre();
      for(int i=1 ; i<= testCase ; i++)
        myCode();

    return 0;
}