#include <bits/stdc++.h>
using namespace std;

using ll = long long int;
using ull = unsigned long long int;
using P = pair<int, int>;
using P3 = pair<double,P>;
using PP = pair<P, P>;
constexpr int INF = 1 << 30;
constexpr ll MOD = ll(1e9)+7;

int main(){
    int N, D, K;
    cin >> N >> D >> K;
    vector<vector<ll> > dp(K+1, vector<ll>(N+1));
    for(int i=0;i<=K;i++){
        dp[i][0] = 1;
    }
    for(int j=0;j<N;j++){
        for(int i=0;i<K;i++){
            if(i < D){
                dp[i+1][j+1] = (dp[i][j] + dp[i][j+1]) % MOD;
            }else{
                dp[i+1][j+1] = (dp[i][j] - dp[i-D][j] + dp[i][j+1] + MOD) % MOD;
            }
        }
    }
    cout << (dp[K][N]-dp[K-1][N]+MOD)%MOD << endl;
    return 0;
}