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#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second

typedef long long ll;

const ll MOD = 1e9 + 7;
const int MAXN = 1000007;

ll P[MAXN];

ll FastPow(ll a, ll b){

	ll res = 1;
	a %= MOD;

	while(b > 0){

		if(b % 2 == 1) res = res * a % MOD;
		a = a * a % MOD;
		b /= 2;
	}

	return res;
}

void solve(){

	ll n, k, m;
	cin >> n >> k >> m;

	ll invK = FastPow(k, MOD - 2), S = 1, Q = 1, ans = 0;
	P[0] = 1;

	for(int v = 0; v < m; v++){

		if(v > 0){

			P[v] = S * invK % MOD;
			S = (S + P[v]) % MOD;
			if(v >= k) S = (S - P[v - k] + MOD) % MOD;
		}

		ll w_count = max(0LL, min((ll)k, (ll)v + k - m + 1));
		ll p_win = w_count * invK % MOD;
		ll T = P[v] * p_win % MOD;

		ll term = 0;
		if(T == 0) term = P[v] * n % MOD * FastPow(Q, n - 1) % MOD;
		else term = P[v] * ((FastPow(Q, n) - FastPow((Q - T + MOD) % MOD, n) + MOD) % MOD) % MOD * FastPow(T, MOD - 2) % MOD;

		ans = (ans + term) % MOD;
		Q = (Q - T + MOD) % MOD;
	}

	cout << ans << '\n';
}

bool multi = 0;

int main(){

	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	int t = 1;
	if(multi) cin >> t;

	while(t--){

		solve();
	}

	return 0;
}