using System;

namespace YukiCorderNo314_20170924 {
    class Program {

        static long courseNum=1;

        static void Main(string[] args) {

            int maxStep = int.Parse(Console.ReadLine());
            KenPa(maxStep);

            Console.WriteLine(courseNum%(10000000000+7));
        }

        static void KenPa(int maxStep) {
            int kenCount=0;
            for (int i = 0; i < maxStep; ) {
                maxStep--;
                //ケン確定
                if (kenCount == 0) {
                    kenCount++;
                }
                //パ確定
                else if (kenCount == 2) {
                    kenCount = 0;
                }
                //分岐確定
                else {
                    courseNum++;
                    kenCount++;
                    //Console.WriteLine("分岐！");
                    KenPa(maxStep);
                }
            }
        }
    }
}