#include <bits/stdc++.h>
using namespace std;
const int inf = (int)1e9;
const double eps = 1e-9;
const double pi = acos(-1.0);
const int mod = (int)1e9 + 7;
int main() {
  int a, b, c, l;
  cin >> a >> b >> c >> l;
  long long ans = 0;
  for (int i = 0; i <= l; i++) {
    ans += (l - i + 1) * 1ll * (l - i + 2) / 2;
  }
  for (int i = 0; i <= l; i++) {
    int cc = a - b - c + i;
    if (cc < 0) continue;
    cc = min(cc, l - i);
    ans -= (cc + 1) * 1ll * (cc + 2) / 2;
  }
  for (int i = 0; i <= l; i++) {
    int cc = b - a - c + i;
    if (cc < 0) continue;
    cc = min(cc, l - i);
    ans -= (cc + 1) * 1ll * (cc + 2) / 2;
  }
  for (int i = 0; i <= l; i++) {
    int cc = c - b - a + i;
    if (cc < 0) continue;
    cc = min(cc, l - i);
    ans -= (cc + 1) * 1ll * (cc + 2) / 2;
  }
  cout << ans << endl;
  return 0;
}
