#include <vector>
#include <iostream>
#include <utility>
#include <algorithm>

using ll = long long;

int n;
std::vector<std::vector<ll>> dp;

int main() {
    std::cin >> n;
    dp.assign(n+1, std::vector<ll>(4, 0));
    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]) % 1000000007);
        dp[i+1][2] += ((dp[i][1] + dp[i][3]) % 1000000007);
        dp[i+1][3] += ((dp[i][1] + dp[i][2]) % 1000000007);
    }
    ll ans = dp[n][1] + dp[n][2] + dp[n][3];
    std::cout << ans << std::endl;
}