#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)(n);++i)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;--i)
#define srep(i,s,t) for(int i=(int)(s);i<(int)(t);++i)
#define each(a,b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define len(v) (int)(v).size()
#define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end())
#define fi first
#define se second
#define pb push_back
#define show(x) cout<<#x<<" = "<<(x)<<endl
#define spair(p) cout<<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout<<" "<<kbrni;cout<<endl
#define smap(m) cout<<#m<<":";each(kbrni,m)cout<<" {"<<kbrni.first<<":"<<kbrni.second<<"}";cout<<endl

using namespace std;

typedef pair<int,int> P;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<double> vd;
typedef vector<P> vp;

const int MAX_N = 1000005;

ll dp[MAX_N][3];
//0:けんけん,1:けんぱ,2:ぱけん

ll add(ll x,ll y)
{
    return (x + y)%MOD;
}

ll sub(ll x,ll y)
{
    return (x+MOD-y)%MOD;
}

ll mult(ll x,ll y)
{
    return x*y%MOD;
}


int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    dp[0][1] = 1;
    rep(i,n){
        dp[i+1][0] = add(dp[i+1][0],dp[i][2]);
        dp[i+1][1] = add(dp[i+1][1],add(dp[i][0],dp[i][2]));
        dp[i+1][2] = add(dp[i+1][2],dp[i][1]);
    }
    cout << add(dp[n][0],add(dp[n][1],dp[n][2])) << endl;
    return 0;
}