#include <bits/stdc++.h>
using namespace std;
int main(int argc, char *argv[]) {
  int n, m, s;
  cin >> n >> m >> s;
  long long ans = 0;
  for (int a = 0; a * 2 < n; a++) {
    for (int b = 0; b * 2 < m; b++) {
      int area = (2 * a + 1) * (2 * b + 1);
      if (area < s) {
        if ((s - area) & 1) continue;
        for (int c = 0; c < a; c++) {
          if ((s - area) % (2 * c + 1)) continue;
          int d = (s - area) / 2 / (2 * c + 1) + b;
          assert(d > 0);
          int w = 2 * a + 1, h = 2 * d + 1;
          if (w > n || h > m) continue;
          ans += (n - w + 1) * (m - h + 1) * 2;
        }
      } else if (area == s) {
        int w = 2 * a + 1, h = 2 * b + 1;
        int mul = (a + 1) * (b + 1) * 2 - 1;
        ans += (n - w + 1) * (m - h + 1) * mul;
      }
    }
  }
  cout << ans << endl;
  return 0;
}
