#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>
#include <vector>
#include <numeric>

#define ll long long

using namespace std;

int main(){
  
   int k;
   cin>>k;
   double x=(double)7/6;
   double ans=1;
   for(int i=1;i<k;++i) ans*=x;

   printf("%.5lf\n",ans);

   return 0;
}