#include <bits/stdc++.h>
using namespace std;
int main(int argc, char** argv) {
  int n, m, s;
  cin >> n >> m >> s;
  long long aa = 0;
  for (int a = 0; a <= n / 2; a++) {
    for (int b = 0; b <= m / 2; b++) {
      for (int c = 0; c <= n / 2; c++) {
        int l = 0, r = m / 2, ans = 0;
        while (l <= r) {
          int d = (l + r) >> 1;
          int ss = (1 + 2 * max(a, b)) * (1 + 2 * min(a, b)) +
                   (1 + 2 * max(c, d)) * (1 + 2 * min(c, d)) -
                   (1 + 2 * min(a, c)) * (1 + 2 * min(b, d));
          if (ss >= s) {
            ans = d;
            r = d - 1;
          } else {
            l = d + 1;
          }
        }
        l = 0, r = m;
        int ans2 = 0;
        while (l <= r) {
          int d = (l + r) >> 1;
          int ss = (1 + 2 * max(a, b)) * (1 + 2 * min(a, b)) +
                   (1 + 2 * max(c, d)) * (1 + 2 * min(c, d)) -
                   (1 + 2 * min(a, c)) * (1 + 2 * min(b, d));
          if (ss <= s) {
            ans2 = d;
            l = d + 1;
          } else {
            r = d - 1;
          }
        }
        int d = ans;
        if (max(2 * c + 1, 2 * a + 1) > n) continue;
        if (max(2 * b + 1, 2 * d + 1) > m) continue;
        if (s == (1 + 2 * max(a, b)) * (1 + 2 * min(a, b)) +
                     (1 + 2 * max(c, d)) * (1 + 2 * min(c, d)) -
                     (1 + 2 * min(a, c)) * (1 + 2 * min(b, d))) {
          aa += 1ll * (abs(ans - ans2) + 1) * (n - 2 * max(a, c)) *
                (m - 2 * max(b, d));
        }
      }
    }
  }
  cout << aa;
  return 0;
}
