#include <bits/stdc++.h> #define REP(i,n,N) for(int i=(n);i<(int) N;i++) #define RREP(i,n,N) for(int i=N-1;i>=(int) n;i--) #define p(s) cout<<(s)<<endl #define DEBUG(x,y) cout<<#x<<": "<<x<<" , "<<#y<<": "<<y<<endl; #define CK(n,a,b) ((a)<=(n)&&(n)<(b)) #define F first #define S second typedef long long ll; using namespace std; const ll mod=1e9+7; int main(){ int M,N; cin>>M>>N; double m = M; REP(i,0,N){ m = (m*2 + m+1)/3; } printf("%.9lf",m); return 0; }