#include <bits/stdc++.h>
int a, b, c, l;
long long sum = 1;
long long calc(int x, int y, int z, int rest) {
  if (x < y + z) return 0ll;
  long long res = std::min(x - y - z, rest);
  return (res + 1) * (long long)(res + 2) >> 1;
}
int main() {
  scanf("%d%d%d%d", &a, &b, &c, &l);
  for (int i = 1; i <= l; i++)
    sum = sum + ((i + 1) * (long long)(i + 2) >> 1ll);
  for (int i = 0; i <= l; i++) {
    sum -= calc(a + i, b, c, l - i);
    sum -= calc(b + i, c, a, l - i);
    sum -= calc(c + i, a, b, l - i);
  }
  printf("%lld\n", sum);
  return 0;
}
