#include <iostream>
#include <vector>

using namespace std;

using int64 = long long;

const int MOD = 1000000007;
int main() {
    int n, d, k;
    cin >> n >> d >> k;
    vector<vector<int64>> dp(n + 1, vector<int64>(k + d + 1, 0));
    dp[0][0] = 1;

    for (int i=0; i<n; i++) {
        for (int j=0; j<=d*n; j++) {
            if (j > k-1) continue;
            dp[i+1][j+1] += dp[i][j];
            dp[i+1][j+1+d] -= dp[i][j];
            dp[i+1][j+1] += dp[i+1][j];

            dp[i+1][j+1] %= MOD;
        }
    }
    while(dp[n][k] < 0) dp[n][k] += MOD;

    cout << dp[n][k] << endl;
}