using System;

class KenKenPa2
{
	const int M = 1000000007;
	static int N;

	static void Main(String[] args)
	{
		N = int.Parse(Console.ReadLine());
		long[,,] dp = new long[2,2,N+1];
		
		dp[0,0,N] = 1;
		dp[0,1,N] = 1;
		dp[1,0,N] = 1;
		for(int i=N-1; i>=2; i--)
		{
			dp[0,0,i] = dp[1,0,i+1];
			dp[0,1,i] = (dp[0,0,i+1] + dp[1,0,i+1]) % M;
			dp[1,0,i] = dp[0,1,i+1];
		}
		dp[0,0,1] = (dp[1,0,2] + dp[0,0,2]) % M;
		dp[0,0,0] = dp[0,0,1];
		Console.WriteLine(dp[0,0,0]);
	}
}