#include<bits/stdc++.h>
using namespace std;
#define fs first
#define sc second
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define ALL(A) A.begin(),A.end()
#define RALL(A) A.rbegin(),A.rend()
typedef long long LL;
typedef pair<LL,LL> P;
const LL mod=1000000007;
const LL LINF=1LL<<60;
const int INF=1<<30;
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};


int main(){
    LL n,d,k;cin >> n >> d >> k;
    vector<vector<LL>> dp(n + 1, vector<LL> (k + 1, 0));
    dp[0][0] = 1;
    for (int i = 0; i < n; i++) {
        LL sum = 0;
        for (int j = 0; j <= k; j++) {
            dp[i + 1][j] = sum;
            sum = (sum + dp[i][j])%mod;
            if(j - d >= 0) sum = (sum + mod - dp[i][j-d])%mod;
        }
    }
    cout << dp[n][k] << endl;
    return 0;
}