#include <iostream>
#include <algorithm>
using namespace std;
const long mod=1e9+7;
long dp[1000010][3];

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