#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<ctime>
#include<cctype>
#include<climits>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<memory>
#include<functional>
 
using namespace std;
 
#define ALL(g) (g).begin(),(g).end()
#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i,n) REP(i,0,n)
#define F(i,j,k) fill(i[0],i[0]+j*j,k)
#define P(p) cout<<(p)<<endl;
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define INF 1<<25
#define pb push_back
 
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<double> vd;
typedef pair<int,int> pii;
typedef pair<long,long> pll;
typedef long long ll;
#define mod 1000000007
	int a[5][2];
	ll dp[100001][4];

int main(){
	int n;
	cin>>n;
	dp[1][1]=1;
	dp[2][2]=1;
	dp[3][3]=1;
	for(int i=1;i<n;i++){
		dp[i+1][1]=(dp[i][2]+dp[i][3])%mod;
		dp[i+2][2]=(dp[i][1]+dp[i][3])%mod;
		dp[i+3][3]=(dp[i][1]+dp[i][2])%mod;
	}
	cout<<dp[n][1]+dp[n][2]+dp[n][3]<<endl;
	return 0;
}