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; 4]; n+1];
    dp[0][0] = 1;
    for i in 0..n {
        for from in 0..4 {
            if dp[i][from] == 0 { continue; }
            for to in 1..4 {
                if from == to { continue; }
                if i + to <= n {
                    dp[i+to][to] += dp[i][from];
                    dp[i+to][to] %= MOD;
                }
            }
        }
    }
    println!("{}", dp[n].iter().sum::<usize>() % MOD);
}