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

using namespace std;

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

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

  printf("%.20f\n", M);
}