package no_0314;

import java.math.BigInteger;
import java.util.Scanner;

public class KenkenPa03 {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

//		while(true) {
		int N = sc.nextInt();

		BigInteger ways = new BigInteger("0");
		BigInteger[][] prev = {{new BigInteger("0"), new BigInteger("0")},
					    {new BigInteger("1"), new BigInteger("1")}};


		if(N == 1) {
			ways = new BigInteger("1");
			System.out.println(ways);
			return;
		}else if(N == 2) {
			ways = new BigInteger("2");
			System.out.println(ways);
			return;
		}

		for(int i = 3; i <= N; i++) {
			BigInteger[][] temp = new BigInteger[2][2];
			temp[1][1] = prev[0][1];
			temp[1][0] = prev[0][1];
			temp[1][0] = temp[1][0].add(prev[1][1]);
			temp[0][1] = prev[1][0];
			prev = temp.clone();
		}

//		for(long[] p: prev) {
//			ways += LongStream.of(p).sum();
//		}
//		for(long[] p: prev) {
//			System.out.println(Arrays.toString(p));
//		}


		ways = ways.add(prev[0][1]);
		ways = ways.add(prev[1][0]);
		ways = ways.add(prev[1][1]);

		System.out.println(ways.mod(new BigInteger("1000000007")));
//	}
	}

}