#include<bits/stdc++.h> #define rep(i,a,b) for(int i=a;i<b;i++) #define rrep(i,a,b) for(int i=a;i>=b;i--) #define fore(i,a) for(auto &i:a) #pragma GCC optimize ("-O3") using namespace std; void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); } //--------------------------------------------------------------------------------------------------- /*--------------------------------------------------------------------------------------------------- ∧_∧ ∧_∧ (´<_` ) Welcome to My Coding Space! ( ´_ゝ`) / ⌒i / \ | | / / ̄ ̄ ̄ ̄/ | __(__ニつ/ _/ .| .|____ \/____/ (u ⊃ ---------------------------------------------------------------------------------------------------*/ int M, N; //--------------------------------------------------------------------------------------------------- void _main() { cin >> M >> N; double ans = M; rep(i, 0, N) ans = ans * 2 * 1.0 / 3.0 + (ans + 1) * 1.0 / 3.0; printf("%.10f\n", ans); }