#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  while (cin >> n) {
    int c = 0;
    for (int i = 0; i <= n && i <= 1000; i++)
      for (int j = 0; j <= n && j <= 1000; j++)
        for (int k = 0; k <= n && k <= 1000; k++) {
          if (n - i - j - k >= 0 && n - i - j - k <= 1000) c++;
        }
    cout << c << endl;
  }
  return 0;
}
