#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:134217728")
using namespace std;
int main() {
  int n, m, s;
  cin >> n >> m >> s;
  long long res = 0;
  for (int a = 0; 1 + 2 * a <= n; a++) {
    for (int b = 0; 1 + 2 * b <= m; b++) {
      int w = 1 + 2 * a;
      int h = 1 + 2 * b;
      if (w * h == s) {
        res += 2 * (long long)(a + 1) * (b + 1) * (n - w + 1) * (m - h + 1);
        res -= (n - w + 1) * (m - h + 1);
      }
      if (w * h < s) {
        int need = s - w * h;
        for (int c = 0; c < a; ++c) {
          if (need % (1 + 2 * c) == 0) {
            int k = need / (1 + 2 * c);
            if (k % 2 == 0 && k + h <= m)
              res += 2 * (m - k - h + 1) * (n - w + 1);
          }
        }
      }
    }
  }
  cout << res << endl;
  return 0;
}
