import java.io.*;
import java.util.*;


public class Main_yukicoder560 {

	private static Scanner sc;
	private static Printer pr;

	private static void solve() {
		int m = sc.nextInt();
		int n = sc.nextInt();

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

		pr.printf("%.9f\n", e);
	}

	// ---------------------------------------------------
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		pr = new Printer(System.out);

		solve();

		pr.close();
		sc.close();
	}

	private static class Printer extends PrintWriter {
		Printer(PrintStream out) {
			super(out);
		}
	}
}