#include <bits/stdc++.h>
using namespace std;
int n, m, s;
int main() {
  scanf("%d%d%d", &n, &m, &s);
  long long ans = 0;
  for (int i = 1; i <= n; i += 2) {
    for (int j = 1; j <= m; j += 2) {
      if (i * j > s) continue;
      if (i * j == s)
        ans += 1ll * ((((i + 1) / 2) * ((j + 1) / 2) * 2 - 1) * (n - i + 1) *
                      (m - j + 1));
      else {
        int t = s - i * j;
        if (t % 2) continue;
        t /= 2;
        for (int k = 1; k < j; k += 2) {
          if (t % k) continue;
          int d = t / k;
          if (2 * d + i <= n)
            ans += 1ll * (n - 2 * d - i + 1) * (m - j + 1) * 2;
        }
      }
    }
  }
  printf("%lld\n", ans);
  return 0;
}
