#include <iostream>
#include <algorithm>

using namespace std;

typedef long long ll;

const ll MOD = 1000000007;

// number of scenes (incl. flat) with n inches left, and k columns left
ll memo[10001][101];        
int n, w, h;

int main()
{
  cin >> n >> w >> h;

  // base cases
  for (int nn = 0; nn <= n; nn++) {
    memo[nn][0] = 1;
  }
  for (int ww = 0; ww <= w; ww++) {
    memo[0][ww] = 1;
  }
  for (int nn = 1; nn <= n; nn++) {
    memo[nn][1] = min(h, nn) + 1;
  }

  for (int ww = 2; ww <= w; ww++) {
    for (int nn = 1; nn <= n; nn++) {
      memo[nn][ww] = (memo[nn-1][ww] + memo[nn][ww-1]) % MOD;
      if (nn - (h+1) >= 0) {
	memo[nn][ww] = (memo[nn][ww] - memo[nn - (h+1)][ww-1]) % MOD;
      }
    }
  }
  
  ll temp = min(h, n/w) + 1;
  ll ans = memo[n][w] - temp;
  if (ans < 0) ans += MOD;

  cout << ans << endl;
  return 0;
}