#include <bits/stdc++.h>
#define FOR(i,bg,ed) for(ll i=(bg);i<(ed);i++)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007
#define int long long
using namespace std;
typedef long long ll;
typedef vector<vector<ll>> mat;
const int INF = 1e9;

int M, N;

double dp[1010];

signed main()
{
    cin >> M >> N;

    dp[0] = M;
    for (int i=1; i<=N; i++) {
        dp[i] = dp[i-1] * 2.0 / 3.0 + (dp[i-1] + 1.0) / 3.0;
    }

    printf("%.10lf\n", dp[N]);
}