#include <iostream>
#include <vector>
#include <algorithm>
#include <atcoder/modint>
using namespace std;
using i64 = long long;
using m32 = atcoder::static_modint<998244353>;
#define rep(i,n) for(int i=0; i<(int)(n); i++)


int main(){
    i64 N; cin >> N;
    i64 M; cin >> M;
    vector<i64> A;
    A.push_back(M);
    while(A.back() != 1) A.push_back((A.back() + 1) / 2);
    A.pop_back();
    if(A.size() >= N){
        A = {1};
        while(A.size() < N) A.push_back(A.back() * 2);
        i64 ans = 0;
        for(auto a : A) ans += a;
        cout << ans << endl;
        return 0;
    }
    i64 ans = 0;
    for(auto a : A) ans += a - 1;
    ans += N;
    cout << ans << endl;
    return 0;
}


struct ios_do_not_sync{
    ios_do_not_sync(){
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} ios_do_not_sync_instance;