#include <bits/stdc++.h>
using namespace std;
long long find(long long n) {
  if (n < 2)
    return 0;
  else
    return (n * (n - 1)) / 2;
}
int main() {
  long long a, b, c, l;
  cin >> a >> b >> c >> l;
  long long ans = ((l + 1) * (l + 2) * (l + 3)) / 6;
  for (int i = 0; i <= l; i++) {
    ans = ans - find(min(a - b - c + i, l - i) + 2) -
          find(min(b - c - a + i, l - i) + 2) -
          find(min(c - a - b + i, l - i) + 2);
  }
  cout << ans << endl;
}
