#include <iostream>

#include <cstdio>

#include <sstream>

#include <cstring>

#include <map>

#include <set>

#include <vector>

#include <stack>

#include <queue>

#include <algorithm>

#include <cmath>

#define MOD 2018

#define LL long long

#define ULL unsigned long long

#define maxn 100000000

#define Pair pair<int, int>

#define mem(a, b) memset(a, b, sizeof(a))

#define _  ios_base::sync_with_stdio(0),cin.tie(0)

//freopen("1.txt", "r", stdin);

using namespace std;

const int LL_INF = 0x7fffffffffffffff,INF = 0x3f3f3f3f;

double ch[maxn/+];

int main()

{

    int T, cnt = ;

    double sum = ;

    ch[] = ;

    for(int i=; i<=maxn; i++)

    {

        sum += /(double)i;

        if(i %  == )

            ch[cnt++] = sum;

    }

    int kase = ;

    cin>> T;

    while(T--)

    {

        int n;

        cin>> n;

        double m = ch[n/];

        for(int i=n/*+; i<=n; i++)

            m += /(double)i;

        printf("Case %d: %.10f\n",++kase,m);    

    }

    return ;

}