#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned long long int n, k, d, i, j, x;
  cin >> n >> k >> d;
  unsigned long long int dp[n + 1][k + 1];
  dp[0][1] = 0;
  for (i = 0; i <= n; i++) dp[i][0] = 1;
  for (i = 1; i <= n; i++) {
    unsigned long long int sum = 0;
    for (j = 1; j <= min(i, k); j++) {
      if (j == i)
        sum = (sum + 1) % 1000000007;
      else
        sum = (sum + dp[i - j][1]) % 1000000007;
    }
    dp[i][1] = sum % 1000000007;
  }
  for (i = 1; i <= k; i++) dp[0][i] = 0;
  for (j = 2; j <= k; j++) {
    for (i = 1; i <= n; i++) {
      unsigned long long int sum = 0;
      for (x = 1; x <= min(i, k); x++) {
        if (x < j)
          sum = (sum + dp[i - x][j]) % 1000000007;
        else if (x != i)
          sum = (sum + dp[i - x][1]) % 1000000007;
        else if (x == i)
          sum = (sum + 1) % 1000000007;
      }
      dp[i][j] = sum;
    }
  }
  cout << dp[n][d] << '\n';
  return 0;
}
