#include <bits/stdc++.h>
using namespace std;

int main() {
    constexpr int64_t mod = 1000000007;
    int n;
    cin >> n;
    vector<vector<int64_t>> ans(n + 3, vector<int64_t>(4));
    ans.at(n).at(0) = 1;
    for (int i = n - 1; i >= 0; i--) {
        for (int j = 1; j <= 3; j++) {
            for (int k = 0; k <= 3; k++) {
                if (j == k) continue;
                ans.at(i).at(j) += ans.at(i + j).at(k);
            }
            ans.at(i).at(j) %= mod;
        }
    }
    cout << (ans.at(0).at(1) + ans.at(0).at(2) + ans.at(0).at(3)) % mod << endl;
}