/* -*- coding: utf-8 -*-
 *
 * 560.cc: No.560 ふしぎなナップサック - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

/* global variables */

/* subroutines */

/* main */

int main() {
  double m;
  int n;
  cin >> m >> n;

  for (int i = 0; i < n; i++)
    m = (m * 2 + (m + 1) + 0) / 3;

  printf("%.12lf\n", m);
  return 0;
}