#include <cstdio>

using i64 = long long;

int main() {
  int N, K, D;
  while (~scanf("%d %d %d", &N, &K, &D)) {
    int times = (N - 1) / (K - 1);
    int rest = N - (K - 1) * times;
    if (D == 1) {
      printf("%d\n", rest);
    } else {
      static int pows[1000010], invs[1000010];
      const int mod = 1e9 + 7;
      pows[0] = 1;
      for (int i = 1; i <= times; ++i) {
        pows[i] = i64(pows[i - 1]) * D % mod;
      }
      invs[1] = 1;
      for (int i = 2; i <= times; ++i) {
        invs[i] = i64(invs[mod % i]) * (mod - mod / i) % mod;
      }
      int binom = 1;
      __int128_t ans = 0;
      for (int i = 0; i <= times; ++i) {
        ans += i64(pows[times - i]) * binom;
        binom = i64(binom) * (rest - 1 + i) % mod * invs[i + 1] % mod;
      }
      ans *= rest;
      printf("%d", int(ans % mod));
    }
  }
  return 0;
}