#include <bits/stdc++.h>
using namespace std;
long long a, b, c, l, ans;
long long min(long long a, long long b) { return a < b ? a : b; }
int main() {
  scanf("%lld%lld%lld%lld", &a, &b, &c, &l);
  for (int i = 0; i <= l; ++i) ans += 1ll * (1ll * i + 1) * (1ll * i + 2) / 2;
  for (int i = 0; i <= l; ++i) {
    if (a + i < b + c) continue;
    long long tb = min(a - b - c + 1ll * i, l - i * 1ll);
    ans -= (tb + 1) * (tb + 2) / 2;
  }
  for (int i = 0; i <= l; ++i) {
    if (c + i < a + b) continue;
    long long tb = min(c - a - b + 1ll * i, 1ll * l - 1ll * i);
    ans -= (tb + 1) * (tb + 2) / 2;
  }
  for (int i = 0; i <= l; ++i) {
    if (b + i < a + c) continue;
    long long tb = min(b - a - c + 1ll * i, 1ll * l - 1ll * i);
    ans -= (tb + 1) * (tb + 2) / 2;
  }
  printf("%lld", ans);
  return 0;
}
