using System;
using System.Text;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using static System.Console;
using static System.Math;

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            new ABC122().SolveD(new ConsoleInput(Console.In, ' '));
        }
    }

    public class ConsoleInput
    {
        private readonly System.IO.TextReader _stream;
        private char _separator = ' ';
        private Queue<string> inputStream;
        public ConsoleInput(System.IO.TextReader stream, char separator = ' ')
        {
            this._separator = separator;
            this._stream = stream;
            inputStream = new Queue<string>();
        }
        public string Read
        {
            get
            {
                if (inputStream.Count != 0) return inputStream.Dequeue();
                string[] tmp = _stream.ReadLine().Split(_separator);
                for (int i = 0; i < tmp.Length; ++i)
                    inputStream.Enqueue(tmp[i]);
                return inputStream.Dequeue();
            }
        }
        public string ReadLine { get { return _stream.ReadLine(); } }
        public int ReadInt { get { return int.Parse(Read); } }
        public long ReadLong { get { return long.Parse(Read); } }
        public double ReadDouble { get { return double.Parse(Read); } }
        public string[] ReadStrArray(long N) { var ret = new string[N]; for (long i = 0; i < N; ++i) ret[i] = Read; return ret; }
        public int[] ReadIntArray(long N) { var ret = new int[N]; for (long i = 0; i < N; ++i) ret[i] = ReadInt; return ret; }
        public long[] ReadLongArray(long N) { var ret = new long[N]; for (long i = 0; i < N; ++i) ret[i] = ReadLong; return ret; }
    }
  class ABC122
    {
        public void SolveD(ConsoleInput cin)
        {
            var n = cin.ReadInt;
            var MOD = (int)(Pow(10, 9) + 7);
            var dp = new int[n + 1, 4, 4, 4];
            //T=0 A=1 G=2 C=3
            //NG: AGC,ACG,GAC,AxGC,AGxC
            //NG: 123,132,213,1x23,12x3
            dp[0, 0, 0, 0] = 1;
            //DP法
            for (int i = 0; i < n; i++)
            {
                for (int a = 0; a < 4; a++)
                {
                    for (int b = 0; b < 4; b++)
                    {
                        for (int c = 0; c < 4; c++)
                        {
                            for (int d = 0; d < 4; d++)
                            {
                                //３文字のNGパターン
                                if (ng(b, c, d) || ng(b, d, c) || ng(c, b, d)) continue;
                                //４文字のNGパターン
                                if (ng(a, c, d) || ng(a, b, d)) continue;
                                dp[i + 1, b, c, d] = (dp[i + 1, b, c, d] + dp[i, a, b, c]) % MOD;
                            }
                        }
                    }
                }
            }
            var sum = 0;

            for (int a = 0; a < 4; a++)
            {
                for (int b = 0; b < 4; b++)
                {
                    for (int c = 0; c < 4; c++)
                    {
                        sum = (sum + dp[n, a, b, c]) % MOD;
                    }
                }
            }

            WriteLine(sum);
            ReadLine();
        }

        bool ng(int a, int b, int c)
        {
            return (a == 1 && b == 2 && c == 3);
        }
    }
}

Measured memory_bytes: 11324