#include<bits/stdc++.h>
using namespace std;

#define int long long

#define rep(i,n) for(int i=0;i<(n);i++)
#define pb push_back
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
typedef vector<int>vint;
typedef pair<int,int>pint;
typedef vector<pint>vpint;

template<typename A,typename B>inline void chmin(A &a,B b){if(a>b)a=b;}
template<typename A,typename B>inline void chmax(A &a,B b){if(a<b)a=b;}

double dp[64];
double nex[64];

signed main(){
    dp[0]=1;
    int N;cin>>N;
    rep(t,N){
        memset(nex,0,sizeof(nex));
        rep(i,64){
            double tmp=dp[i]/6;
            for(int j=0;j<6;j++)nex[i|(1<<j)]+=tmp;
        }
        rep(i,64)dp[i]=nex[i];
    }

    printf("%.20f\n",dp[63]);
    return 0;
}