#include <bits/stdc++.h>

using namespace std;

const long long MOD = 1e9 + 7;

long long dp[1000001][3];

int main() {
    int n;
    cin >> n;

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < 3; ++j) {
            dp[i][j] = 0;
        }
    }

    dp[1][1] = 1;// K
    for (int i = 1; i < n; ++i) {
        dp[i + 1][1] += dp[i][0];// P->K
        dp[i + 1][1] %= MOD;

        dp[i + 1][0] += dp[i][1] + dp[i][2];// K->P, KK->P
        dp[i + 1][0] %= MOD;
        
        dp[i + 1][2] += dp[i][1];// K->KK
        dp[i + 1][2] %= MOD;
    }

    long long ans = 0;
    for (int i = 0; i < 3; ++i) {
        ans = (ans + dp[n][i]) % MOD;
    }
    cout << ans << endl;
    return 0;
}