#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <cmath>
#include <numeric>
#include <utility>
#include <iomanip>

using namespace std;
using int64 = long long;

struct aaa{aaa(){cin.tie(nullptr); ios::sync_with_stdio(false); cout<<fixed<<setprecision(20);};}aaa;

int main() {
    int n;
    cin >> n;
    int ans = 0;
    for (int x=0; x<=n; x++) {
        for (int y=0; y<=n-x; y++) {
            ans++;
        }
    }
    cout << ans << endl;
}