typedef long long ll;
typedef long double ld;
#include <bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
    ll n,m;
    std::cin >> n>>m;
    ll ans = 0;
    ll las;
    if(n>30){
        las = m;
    }else{
        las = min(m,1ll<<(n-1));
    }
    for (int i = 0; i <n; i++) {
        ans += las;
        las = (las+1)/2;
    }
    std::cout << ans << std::endl;
}