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#include <bits/stdc++.h>

#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())

using namespace std;

#ifdef LOCAL
template<typename A, typename B>
auto&operator<<(auto&o,pair<A, B>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<&","[!i++]<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

using i64 = long long;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<i64, i64>;
using vi = vector<int>;
using vll = vector<i64>;

const i64 MOD = 1'000'000'007;

void add_mod(i64 &a, i64 b) {
	a += b;
	if (a >= MOD) {
		a -= MOD;
	}
}

void sub_mod(i64 &a, i64 b) {
	a -= b;
	if (a < 0) {
		a += MOD;
	}
}

i64 mul_mod(i64 a, i64 b) {
	return (a * b) % MOD;
}

i64 pow_mod(i64 a, i64 n) {
	i64 r = 1;
	while (n) {
		if (n % 2 == 1) {
			r = mul_mod(a, r);
		}
		n /= 2;
		a = mul_mod(a, a);
	}
	return r;
}

i64 inv_mod(i64 a) {
	return pow_mod(a, MOD - 2);
}

struct ProbEV {
	i64 prob;
	i64 ev;

	ProbEV() : prob{0}, ev{0} {}
	ProbEV(i64 prob_, i64 ev_) : prob{prob_}, ev{ev_} {}

	ProbEV &operator*=(const ProbEV &other) {
		ev = (prob * other.ev + other.prob * ev) % MOD;
		prob = mul_mod(prob, other.prob);
		return *this;
	}

	ProbEV operator*(const ProbEV &other) const {
		ProbEV ret = *this;
		ret *= other;
		return ret;
	}

	ProbEV &operator*=(int p) {
		ev = mul_mod(ev, p);
		prob = mul_mod(prob, p);
		return *this;
	}

	ProbEV operator*(int p) const {
		ProbEV ret = *this;
		ret *= p;
		return ret;
	}

	ProbEV &operator+=(const ProbEV &other) {
		add_mod(prob, other.prob);
		add_mod(ev, other.ev);
		return *this;
	}

	ProbEV operator+(const ProbEV &other) const {
		ProbEV ret = *this;
		ret += other;
		return ret;
	}

	ProbEV &operator-=(const ProbEV &other) {
		sub_mod(prob, other.prob);
		sub_mod(ev, other.ev);
		return *this;
	}

	ProbEV operator-(const ProbEV &other) const {
		ProbEV ret = *this;
		ret -= other;
		return ret;
	}

	friend ostream &operator<<(ostream &os, const ProbEV &val) {
		os << "(p=" << val.prob << ", ev=" << val.ev << ")";
		return os;
	}
};

// \sum_{i=0}^n A^i B^{n-i}. Assume that One is identity wrt multiplication
template <typename T>
T GeomABSum(T A, T B, T one, i64 n) {
	// More general: given also C, D, compute
	// (\sum_{i=0}^n A^i B^{n-i}) * C  +  D * B^n
	T C = one, D = T{};
	while (n) {
		if (n % 2 == 1) {
			C *= (A + B);
			D *= B;
			A *= A;
			B *= B;
			n /= 2;
		} else {
			D = (D + C) * B;
			C *= A;
			--n;
		}
	}
	return C + D;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout << fixed << setprecision(14);
	cerr << fixed << setprecision(6);

	int N, K, M;
	cin >> N >> K >> M;

	const ProbEV one_step{1, 1};
	const ProbEV prob_divk{inv_mod(K), 0};
	const ProbEV step_divk = prob_divk * one_step;

	vector<ProbEV> jump_to(M + 1);
	ProbEV jump_to_cur_intv;
	jump_to[0] = ProbEV{1, 0};
	for (int s = 1; s <= M; ++s) {
		jump_to_cur_intv += jump_to[s - 1];
		jump_to[s] = jump_to_cur_intv * step_divk;
		if (s >= K) {
			jump_to_cur_intv -= jump_to[s - K];
		}
	}

	vector<ProbEV> jump_no_finish(M + 1);

	jump_no_finish[0] = ProbEV{1, 0};
	for (int i = 0; i < M; ++i) {
		const int last = min(M - 1, i + K);
		const ProbEV coef = jump_to[i] * step_divk;
		jump_no_finish[last] += coef;
		jump_no_finish[i] -= coef * (last - i + 1);
		if (i) {
			jump_no_finish[i - 1] += coef * (last - i);
		}
	}
	for (int iter = 0; iter < 2; ++iter) {
		for (int i = M; i > 0; --i) {
			jump_no_finish[i - 1] += jump_no_finish[i];
		}
	}

	ProbEV ans;
	for (int s = max(0, M - K); s < M; ++s) {
		const int nopts = s + K - M + 1;
		ProbEV coef = jump_to[s] * prob_divk * nopts * one_step;
		coef *= GeomABSum(jump_no_finish[s], jump_no_finish[s + 1], ProbEV{1, 0}, N - 1);
		ans += coef;
	}

	debug(ans);
	assert(ans.prob == 1);
	cout << ans.ev << "\n";
}