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

double f(int n, double x) {
  if (n == 0) {
    return x;
  }
  return f(n - 1, 2.0 / 3 * x + 1.0 / 3 * (x + 1));
}
int main() {
  int m, n;
  cin>>m>>n;
  printf("%.9lf\n", 1.0 * m + f(n, 0.0));
}