#pragma warning disable IDE0011
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Numerics;

class ReaderWriter
{
    protected int _Index;
    protected string[] _Line;

    public void R(char sep = ' ') { _Line = Console.ReadLine().Split(sep); _Index = 0; }
    public string S() => _Line[_Index++];
    public string[] Ss() => _Line.Skip(_Index++).ToArray();
    public char C() => char.Parse(_Line[_Index++]);
    public char[] Cs() => _Line.Skip(_Index++).Select(char.Parse).ToArray();
    public int I() => int.Parse(_Line[_Index++]);
    public int[] Is() => _Line.Skip(_Index++).Select(int.Parse).ToArray();
    public long L() => long.Parse(_Line[_Index++]);
    public long[] Ls() => _Line.Skip(_Index++).Select(long.Parse).ToArray();
    public double F() => double.Parse(_Line[_Index++]);
    public double[] Fs() => _Line.Skip(_Index++).Select(double.Parse).ToArray();
    public decimal D() => decimal.Parse(_Line[_Index++]);
    public decimal[] Ds() => _Line.Skip(_Index++).Select(decimal.Parse).ToArray();
    public BigInteger B() => BigInteger.Parse(_Line[_Index++]);
    public BigInteger[] Bs() => _Line.Skip(_Index++).Select(BigInteger.Parse).ToArray();

    public void Write(params object[] xs)
    {
        Console.Write(xs.First());
        foreach (var x in xs.Skip(1)) Console.Write(" " + x);
        Console.WriteLine();
    }
}

class Program
{
    static void Main()
    {
        Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
        Solve(new ReaderWriter());
        Console.Out.Flush();
    }

    static void Solve(ReaderWriter rw)
    {
        rw.R(); var n = rw.L();

        const long mod = 1000000007;

        var dp = new long[1000001, 3];
        dp[1, 0] = 1; dp[1, 1] = 0; dp[1, 2] = 0;
        dp[2, 0] = 0; dp[2, 1] = 1; dp[2, 2] = 0;
        dp[3, 0] = 1; dp[3, 1] = 1; dp[3, 2] = 1;

        for (var i = 4; i <= n; i++)
        {
            dp[i, 0] = (dp[i - 1, 1] + dp[i - 1, 2]) % mod;
            dp[i, 1] = (dp[i - 2, 0] + dp[i - 2, 2]) % mod;
            dp[i, 2] = (dp[i - 3, 0] + dp[i - 3, 1]) % mod;
        }

        rw.Write((dp[n, 0] + dp[n, 1] + dp[n, 2]) % mod);
    }
}