#![allow(unused_imports)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;
use std::ops::Bound::*;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let v = read_vec::<i64>();
    let (mut n, m) = (v[0], v[1]);
    let mut ans = 0;
    let mut cur = 1i64;
    for i in 0..n {
        ans += cur;
        if i == n - 1 {
            println!("{}", ans);
            return;
        }
        cur *= 2;
        if cur > m {
            break;
        }
    }

    let mut ans = 0;
    let mut cur = m;
    while cur > 1 && n > 0 {
        ans += cur;
        cur = (cur + 1) / 2;
        n -= 1;
    }
    debug!(ans, n);
    println!("{}", ans + n);
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}