using System;
using System.IO;

class Program
{
    static void Solve()
    {
        int n = sc.Int();

        long[,] dp = new long[3, n + 5];

        for (int i = 1; i <= 3; i++)
            dp[i-1, i] = 1;


        for (int i = 1; i < n; i++)
            for (int j = 0; j < 3; j++)
                for (int k = 0; k < 3; k++)
                    if (j != k)
                        dp[k, i + k + 1] += dp[j, i] % MOD;

        long ans = 0;

        for (int i = 0; i < 3; i++)
            ans += dp[i, n];

        ans %= MOD;

        pr.WriteLine(ans);
    }


    static void Main(string[] args)
    {
        Solve();
        pr.Flush();
    }

    static Scanner sc = new Scanner();
    static Printer pr = new Printer();
    static readonly int MOD = 1000000007;
}

#region IO
class Scanner
{
    private int _i = 0; 
    private string[] line = new string[0];

    private T[] Enumerate<T>(int n, Func<T> f)
    {
        T[] ret = new T[n];
        for (int i = 0; i < n; i++)
            ret[i] = f();
        return ret;
    }

    public string String()
    {
        if (line.Length <= _i)
        {
            line = Console.ReadLine().Split(' ');
            _i = 0;
        }

        return line[_i++];
    }

    public int Int() => int.Parse(String());
    public long Long() => long.Parse(String());
    public double Double() => double.Parse(String());
    public int[] Int(int n) => Enumerate(n, Int);
    public long[] Long(int n) => Enumerate(n, Long);
    public double[] Double(int n) => Enumerate(n, Double);
    public string[] String(int n) => Enumerate(n, String);
}

class Printer : StreamWriter
{
    public Printer() : base(Console.OpenStandardOutput())
    {
        AutoFlush = false;
    }
}
#endregion