#include <bits/stdc++.h>
using namespace std;
#define modulo 1000000007
#define mod(mod_x) ((((long long)mod_x+modulo))%modulo)
#define Inf 1000000000


int main(){
    
	int N,d,K;
	cin>>N>>d>>K;
	
	vector<vector<int>> dp(2,vector<int>(K+1,0));
	dp[0][0] = 1;
	
	for(int i=0;i<N;i++){
		for(int j=1;j<=K;j++){
			dp[0][j] = mod(dp[0][j] + dp[0][j-1]);
		}
		
		for(int j=1;j<=K;j++){
			dp[1][j] = dp[0][j-1];
			if(j-d-1>=0){
				dp[1][j] = mod(dp[1][j] - dp[0][j-d-1]);
			}
		}
		/*
		for(int j=0;j<=K+1;j++){
			cout<<dp[1][j]<<',';
		}
		cout<<endl;
		*/
		swap(dp[0],dp[1]);
		for(int j=0;j<=K;j++){
			dp[1][j] = 0;
		}
	}
	
	cout<<dp[0].back()<<endl;
	
    return 0;
}