#include <iostream>
#include <vector>
#include <map>
#include <cstring>
#include <fstream>
#include <sstream>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
#include <unordered_map>
#include <stack>
#include <iomanip>
#include <random>
#include <climits>

using namespace std;

ifstream fin("diamant.in");
ofstream fout("diamant.out");

const int MAX = 401;

int numberOfCombination[MAX];

int main() {
    int n, m;
    long long x;
    fin >> n >> m >> x;

    vector<int> square;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            square.push_back((i + 1) * (j + 1));
        }
    }

    numberOfCombination[0] = 1;
    for (int i = 0; i < (int) square.size(); ++i) {
        for (int j = square[i]; j <= x; ++j) {
            numberOfCombination[j] += numberOfCombination[j - square[i]];
        }
    }

    fout << numberOfCombination[x];

    return 0;
}