use std::cmp::*;
use std::io::*;

fn main() {
    let mut s: String = String::new();
    std::io::stdin().read_to_string(&mut s).ok();
    let mut itr = s.trim().split_whitespace();
    let n: usize = itr.next().unwrap().parse().unwrap();

    let mut out = Vec::new();
    let mut used = vec![false; n * 2 + 1];

    for i in (1..=n).rev() {
        if used[i * 2] {
            break;
        }
        used[i] = true;
        write!(out, "{} ", i).ok();
    }
    out.pop();
    writeln!(out, "").ok();
    stdout().write_all(&out).unwrap();
}