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

constexpr int mod = 1000000007;

int dp[1001][1001];

int main() {
    int N;
    cin >> N;
    dp[0][0] = 1;
    for(int i = 0; i < N; i++) {
        int sum = 0;
        for(int j = 0; j <= N; j++) {
            sum += dp[i][j];
            sum %= mod;
            if(i+j <= N && j >= 3) {
                dp[i+j][j] += sum;
                dp[i+j][j] %= mod;
            }
        }
    }
    int ans = 0;
    for(int i = 0; i <= N; i++) {
        ans += dp[N][i];
        ans %= mod;
    }
    cout << ans << endl;
}