#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  while (cin >> n) {
    int num[4001] = {0};
    for (int i = 0; i <= n; i++)
      for (int j = 0; i + j <= n; j++) {
        num[i + j]++;
      }
    int res = 0;
    for (int i = 0; i <= n; i++) {
      res += num[i] * num[n - i];
    }
    cout << res << endl;
  }
  return 0;
}
