import java.io.*;
import java.util.*;


public class Main_yukicoder533 {

	private static Scanner sc;
	private static Printer pr;

	private static void solve() {
		final int MOD = 1_000_000_007;

		int n = sc.nextInt();

		long[][] dp = new long[3][n + 10];
		dp[0][1] = 1;
		dp[1][2] = 1;
		dp[2][3] = 1;
		for (int i = 1; i <= n; i++) {
			for (int j = 0; j < 3; j++) {
				if (dp[j][i] == 0) {
					continue;
				}

				if (i + (j + 1) % 3 + 1 <= n) {
					dp[(j + 1) % 3][i + (j + 1) % 3 + 1] += dp[j][i];
					dp[(j + 1) % 3][i + (j + 1) % 3 + 1] %= MOD;
				}
				if (i + (j + 2) % 3 + 1 <= n) {
					dp[(j + 2) % 3][i + (j + 2) % 3 + 1] += dp[j][i];
					dp[(j + 1) % 3][i + (j + 1) % 3 + 1] %= MOD;
				}
			}
		}

		pr.println((dp[0][n] + dp[1][n] + dp[2][n]) % MOD);
	}

	// ---------------------------------------------------
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		pr = new Printer(System.out);

		solve();

		pr.close();
		sc.close();
	}

	private static class Printer extends PrintWriter {
		Printer(PrintStream out) {
			super(out);
		}
	}
}