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#include <bits/stdc++.h>
using namespace std;

template <typename T> T mod_inv_in_range(T a, T m) {
    // assert(0 <= a && a < m);
    T x = a, y = m;
    // coeff of a in x and y
    T vx = 1, vy = 0;
    while (x) {
        T k = y / x;
        y %= x;
        vy -= k * vx;
        std::swap(x, y);
        std::swap(vx, vy);
    }
    assert(y == 1);
    return vy < 0 ? m + vy : vy;
}

template <typename T> struct extended_gcd_result {
    T gcd;
    T coeff_a, coeff_b;
};
template <typename T> extended_gcd_result<T> extended_gcd(T a, T b) {
    T x = a, y = b;
    // coeff of a and b in x and y
    T ax = 1, ay = 0;
    T bx = 0, by = 1;
    while (x) {
        T k = y / x;
        y %= x;
        ay -= k * ax;
        by -= k * bx;
        std::swap(x, y);
        std::swap(ax, ay);
        std::swap(bx, by);
    }
    return {y, ay, by};
}

template <typename T> T mod_inv(T a, T m) {
    a %= m;
    a = a < 0 ? a + m : a;
    return mod_inv_in_range(a, m);
}

template <int MOD_> struct modnum {
    static constexpr int MOD = MOD_;
    static_assert(MOD_ > 0, "MOD must be positive");

private:
    int v;

public:

    modnum() : v(0) {}
    modnum(int64_t v_) : v(int(v_ % MOD)) { if (v < 0) v += MOD; }
    explicit operator int() const { return v; }
    friend std::ostream& operator << (std::ostream& out, const modnum& n) { return out << int(n); }
    friend std::istream& operator >> (std::istream& in, modnum& n) { int64_t v_; in >> v_; n = modnum(v_); return in; }

    friend bool operator == (const modnum& a, const modnum& b) { return a.v == b.v; }
    friend bool operator != (const modnum& a, const modnum& b) { return a.v != b.v; }

    modnum inv() const {
        modnum res;
        res.v = mod_inv_in_range(v, MOD);
        return res;
    }
    friend modnum inv(const modnum& m) { return m.inv(); }
    modnum neg() const {
        modnum res;
        res.v = v ? MOD-v : 0;
        return res;
    }
    friend modnum neg(const modnum& m) { return m.neg(); }

    modnum operator- () const {
        return neg();
    }
    modnum operator+ () const {
        return modnum(*this);
    }

    modnum& operator ++ () {
        v ++;
        if (v == MOD) v = 0;
        return *this;
    }
    modnum& operator -- () {
        if (v == 0) v = MOD;
        v --;
        return *this;
    }
    modnum& operator += (const modnum& o) {
        v -= MOD-o.v;
        v = (v < 0) ? v + MOD : v;
        return *this;
    }
    modnum& operator -= (const modnum& o) {
        v -= o.v;
        v = (v < 0) ? v + MOD : v;
        return *this;
    }
    modnum& operator *= (const modnum& o) {
        v = int(int64_t(v) * int64_t(o.v) % MOD);
        return *this;
    }
    modnum& operator /= (const modnum& o) {
        return *this *= o.inv();
    }

    friend modnum operator ++ (modnum& a, int) { modnum r = a; ++a; return r; }
    friend modnum operator -- (modnum& a, int) { modnum r = a; --a; return r; }
    friend modnum operator + (const modnum& a, const modnum& b) { return modnum(a) += b; }
    friend modnum operator - (const modnum& a, const modnum& b) { return modnum(a) -= b; }
    friend modnum operator * (const modnum& a, const modnum& b) { return modnum(a) *= b; }
    friend modnum operator / (const modnum& a, const modnum& b) { return modnum(a) /= b; }
};

template <typename T> T power(T a, long long b) {
    assert(b >= 0);
    T r = 1; while (b) { if (b & 1) r *= a; b >>= 1; a *= a; } return r;
}

const int MOD = 1e9+7;
using mint = modnum<MOD>;

mint solve(int n, int k, int m) {
  vector<mint> V(m), VS(m+1), VSS(m+2);
  V[0] = 1;
  mint s = 1;
  const mint kinv = mint(1) / k;
  for (int i = 1; i < m; i++) {
    V[i] = s * kinv;
    s += V[i];

    if (i >= k) s -= V[i-k];
  }
  for (int i = 0; i < m; i++) VS[i+1] = VS[i] + V[i];
  for (int i = 0; i <= m; i++) VSS[i+1] = VSS[i] + VS[i];

  mint ans = 0;
  for (int mn = 0; mn < m; mn++) {
    mint x = 0, y = V[mn] * k;
    int rl = mn+1, rr = min(mn+k+1, m);
    x += (rr-rl) * VS[mn+1];
    y += (rr-rl) * VS[mn];
    if (rr >= k) {
      rl = max(rl, k);
      x -= (VSS[rr-k] - VSS[rl-k]);
      y -= (VSS[rr-k] - VSS[rl-k]);
    }
    x *= kinv;
    y *= kinv;
    // (x^n-y^n)/(x-y)
    mint pwsum = (x == y ? n * power(x, n-1) : (power(x, n) - power(y, n)) / (x-y));
    ans += V[mn] * pwsum;
  }
  return ans;
}

int main () {
  ios_base::sync_with_stdio(0); cin.tie(0);
  int n, k, m;
  cin >> n >> k >> m;
  cout << solve(n, k, m) << '\n';
}