#include <bits/stdc++.h>
using namespace std;
long long a, b, c, l, tmp;
long long read() {
  long long x = 0, f = 1;
  char ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (isdigit(ch)) x = x * 10 + ch - '0', ch = getchar();
  return x * f;
}
long long cal(long long x, long long y, long long z) {
  if (x < y) return 0;
  long long p = min(z, x - y);
  return (p + 2) * (p + 1) / 2;
}
int main() {
  a = read();
  b = read();
  c = read();
  l = read();
  for (int i = 0; i <= l; i++)
    tmp += cal(a + i, b + c, l - i) + cal(b + i, a + c, l - i) +
           cal(c + i, a + b, l - i);
  printf("%I64d\n", (l + 1) * (l + 2) * (l + 3) / 6 - tmp);
  return 0;
}
