const MOD: usize = 1e9 as usize + 7;

fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();

    let mut dp = vec![vec![0usize; 10]; n];
    for i in 0..=9 { dp[0][i] = 1; }
    for i in 0..n-1 {
        for j in 0..10 {
            if dp[i][j] == 0 { continue; }
            for k in j..10 {
                dp[i+1][k] += dp[i][j];
                dp[i+1][k] %= MOD;
            }
        }
    }
    println!("{}", dp[n-1].iter().sum::<usize>() % MOD);
}