#include <bits/stdc++.h>
using namespace std;
long long work(int a, int b, int c, int l) {
  long long ans = 0;
  for (int i = ((b + c - a > 0) ? (b + c - a) : (0)); i <= l; i++) {
    long long x = ((l - i < a + i - b - c) ? (l - i) : (a + i - b - c));
    ans += (1 + x) * (2 + x) / 2;
  }
  return ans;
}
int main() {
  int a, b, c, l;
  while (scanf("%d%d%d%d", &a, &b, &c, &l) != EOF) {
    long long ans = 0;
    for (int i = 0; i <= l; i++) ans += (long long)(1 + i) * (2 + i) / 2;
    ans -= work(a, b, c, l);
    ans -= work(c, a, b, l);
    ans -= work(b, c, a, l);
    printf("%I64d\n", ans);
  }
  return 0;
}
