#include <iostream>
#include <iomanip>
using namespace std;

int main(){
	int m, n;
	cin >> m >> n;
	double dp[n + 1]{};
	dp[0] = m;
	for(int i = 0; i < n; i++){
		dp[i + 1] = 2 * dp[i] / 3 + (dp[i] + 1) / 3;
	}
	cout << fixed << setprecision(10) << dp[n] << endl;
}