#include <bits/stdc++.h>
using namespace std;
long long sum[500001], ans;
long long solve(long long a, long long b, long long c, long long hh) {
  if (a < b + c) return 0ll;
  long long now = min(a - b - c, hh);
  return (now + 1) * (now + 2) / 2;
}
int main() {
  long long a, b, c, l, i;
  scanf("%lld%lld%lld%lld", &a, &b, &c, &l);
  sum[0] = 1;
  for (i = 1; i <= l; i++) sum[i] = sum[i - 1] + (i + 1) * (i + 2) / 2;
  ans = sum[l];
  for (i = 0; i <= l; i++)
    ans -= solve(a + i, b, c, l - i) + solve(b + i, a, c, l - i) +
           solve(c + i, a, b, l - i);
  printf("%lld", ans);
}
